PRO192.txt

uting SQL statements | jdbc
method is used to wait for a client to initiate communications | accept()
drivers that are written partly in the Java programming language and partly in native code. These drivers use a native client library specific to the data source to which they connect | type 2
drivers that are pure Java and implement the network protocol for a specific data source. The client connects directly to the data source | type 4
drivers that use a pure Java client and communicate with a middleware server using a database-independent protocol. The middleware server then communicates the client's requests to the data source | type 3
drivers that implement the JDBC API as a mapping to another data access API, such as ODBC. Drivers of this type are generally dependent on a native library, which limits their portability | type 1
System.out.println(a.doit(4, 5)) | line 26 prints a to system.out
Which two are true if a NullPointerException is thrown on line 3 of class C | code on line 29, the exception
What lines are output if the constructor at line 3 throws a MalformedURLException | bad url, doing finally, carrying
What lines are output if the methods at lines 3 and 5 complete successfully without throwing any exceptions | success, doing, carrying
If lines 24, 25 and 26 were removed, the code would compile and the output would be 1 | 3.the code, would be 1, 2
An exception is thrown at runtime | an exception
first second first third snootchy 420 | third second first snootchy 420
dialog prevents user input to other windows in the application unitl the dialog is closed | modal
You would like to write code to read back the data from this file. Which solutions will work | 2.fileinputstream, randomaccessfile
A Java monitor must either extend Thread or implement Runnable | false
A monitor called mon has 10 threads in its waiting pool; all these waiting threads have the same priority. One of the threads is thr1 | you cannot specify
A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these ways | public void logit(string... msgs)
A signed data type has an equal number of non-zero positive and negative values available | false
A thread wants to make a second thread ineligible for execution. To do this, the first thread can call the yield() method on the second thread | false
catch (InterruptedException e) | running some time
object is used to submit a query to a database | statement
object is uses to obtain a Connection to a Database | drivermanager
After execution of the following code fragment, what are the values of the variables x, a, and b | x13, a7, b8
Yen and Euro both return correct Country  value | 2.euro returns, error at line 25
BigOlLongStringWithMeaninglessName | tick all
Compilation of class A will fail. Compilation of class B will succeed | b fail, a succeed
Line 46 will compile if enclosed in a try block, where TestException is caught | 2.if the enclosing, is caught
Holder h = new Holder() | 101
Decrementer dec = new Decrementer() | 12.3
Test t = (new Base()).new Test(1) | 2.new test(1), new test(1, 2)
Base(int j, int k, int l) | 2.base(), base(int j, int k)
Line 12 will not compile, because no version of crunch() takes a char argument | output: int version
output results when the main method of the class Sub is run | value 5 this value 6
Float floater = new Float(3.14f) | line 6
The application must be run with the -enableassertions flag or another assertionenabling flag | dai nhat, one or more
After line 3 executes, the StringBuffer object is eligible for garbage collection | line 2 executes..collection
The code will compile but will throw an exception at line 7, because runtime conversion from an interface to a class is not permitted | type swampthing
The code will compile and run, but the cast in line 6 is not required and can be eliminated | the code will compile and run
for (int i = 0; i < 2; i++) | 4.i0,j12 - i1,j02
outer: for (int i = 0; i < 2; i++) | i = 1 j = 0
The code will compile but will throw an exception at line 7, because runtime conversion from an interface to a class is not permitted | line 7 will not compile
int[] x = new int[25] | 2.x[24]=0, x.length is 25
public float aMethod(float a, float b) throws Exception | int a,b float p,q
public float aMethod(float a, float b, int c) throws Exception | 3.int a,b. float a,b-int c. private
Given a string constructed by calling s = new String("xyzzy"), which of the calls modifies the string | none of the above
Given arrays a1 and a2, which call returns true if a1 and a2 have the same length, and a1[i].equals(a2[i]) for every legal index i | arrays.equals(a1, a2)
Assuming the class does not perform custom serialization, which fields are written when an instance of Xyz is serialized | 3.public, private, volatile
can legally be placed before aMethod() on line 3 and be placed before aMethod() on line 8 | 3: private; 8: protected
NUTMEG, CINNAMON, CORIANDER, ROSEMARY | 3.spice sp, spice, string
List<String> names = new ArrayList<String>() | 2.iterator, for
Compilation fails because of an error in line 15 | error in line 19
1 2 3 | 2 3
public interface B inheritsFrom A | b extends a
protected double getSalesAmount() { return 1230.45; } | 2.public, protected
Line 16 creates a directory named “d” and a file ‘f’ within it in the file system | 3.an exception, line 13, line 14
Nav.Direction d = Nav.Direction.NORTH | nav.direction.north
new class Foo { public int bar() { return 1; } } | new foo()
IllegalArgumentException | stackoverflowerror
Circle c = new Circle(); c.Shape.setAnchor(10,10); c.Shape.draw() | shape s = new circle...s.draw()
Compilation fails because of an error in line 12 | 1 2 3
NullPointerException | compilation fails
A NumberFormatException is thrown by the parse method at runtime | compilation fails
An exception is thrown at runtime | compilation fails
passed An AssertionException is thrown without the word “stuff” added to the stack trace | an assertionerror...with the
collie | collie harrier
doStuff x = 6 main x = 6 | dostuff x =5 main x =5
The setCardlnformation method breaks encapsulation | the ownername
The value of all four objects prints in natural order | compilation fails...line 29
The code on line 33 executes successfully | 3.33 throws, 35 throws, 33 executes
What is the result if a NullPointerException occurs on line 34 | ac
Compilation will fail because of an error in line 55 | line 57...value 3
java -ea test file1 file2 | 2.java -ea test, dai nhat
String s = “123456789”; s = (s-”123”).replace(1,3,”24”) - “89” | 2.delete(4,6), delete(2,5).insert( 1, “24”)
The Point class cannot be instatiated at line 15 | line.point p = new line.point()
for( int i=0; i< x.length; i++ )   System.out.println(x[i]) | 2.for(int z : x), dai nhat
int MY_VALUE = 10 | 3.final, static, public
Compilation fails because of an error in line: public void process() throws RuntimeException | a exception
How can you ensure that multithreaded code does not deadlock | there is no single
How can you force garbage collection of an object | garbage collection
How do you prevent shared data from being corrupted in a multithreaded environment | access the variables
How do you use the File class to list the contents of a directory | string[] contents
The number of bytes depends on the underlying system | 8
How many locks does an object have | one
If all three top-level elements occur in a source file, they must appear in which order | package declaration, imports
the two classes are in different packages, and class X has a protected method called abby(), then any instance of Y may call the abby() method of any | false
TestThread3 ttt = new TestThread3 | y
If you need a Set implementation that provides value-ordered iteration, which class should you use | treeset
In order for objects in a List to be sorted, those objects must implement which interface and method | comparable...compareto
after execution of line 1, sbuf references an instance of the StringBuffer class. After execution of line 2, sbuf still references the same instance | true
what are the possible types for variable result | int, long, float, double
helps manage the connection between a Java program and a database | connection
Is it possible to define a class called Thing so that the following method can return true under certain circumstances | y
Is it possible to write code that can execute only if the current thread owns multiple locks | y
JDBC supports ______ and ______ models | two-tier and three-tier
MVC is short call of | model-view-controller
No output because of compile error at line: System.out.println("b="+b) | b = b * b1
Object ob2= new Object() | have a nice day
Object ob2= ob1 | ob1 equals ob2, ob1==ob2
String s2 = "xyz" | line 4, line 6
String s2 = new String("xyz") | line 6
String s2 = new String(s1) | line 6
Select correct statement about RMI | all the above
Select correct statement(s) about remote class | all the others choices
Select correct statements about remote interface | all the others choices
Select INCORRECT statement about  serialization | when an object output
Select INCORRECT statement about deserialize | we use readobject
Select incorrect statement about RMI server | a client accesses
Select incorrect statement about ServerSocket class | to make the new object
Select incorrect statement about Socket class | server through udp
Select the correct statement about JDBC two-tier processing model | a user's commands
SQL keyword ___ is followed by the selection criteria that specify the rows to select in a query | where
Statement objects return SQL query results as | resultset
When a JDBC connection is created, it is in auto-commit mode | both 1 and 2 are true
Suppose a method called finallyTest() consists of a try block, followed by a catch block, followed by a finally block | if the jvm doesn't crash
Suppose a source file contains a large number of import statements and one class definition. How do the imports affect the time required to load the class | no additional time
Suppose a source file contains a large number of import statements. How do the imports affect the time required to compile the source file | slightly more time
Suppose class A extends Object; Class B extends A; and class C extends B. Of these, only class C implements java.io.Externalizable | c must have a
Suppose class A extends Object; class B extends A; and class C extends B. Of these, only class C implements java.io.Serializable | b must have a
Suppose class A has a method called doSomething(), with default access. Suppose class B extends A and overrides doSomething() | private
Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides doSomething() | 2.public, protected
void doSomething(int a, float b) | public...(int a, float b)
Suppose interface Inty defines five methods. Suppose class Classy declares that it implements Inty but does not provide implementations for any of the five interface methods | 2.declared abstract, may not be
Suppose prim is an int and wrapped is an Integer. Which of the following are legal Java statements | all the above
Suppose salaries is an array containing floats. Which of the following are valid loop control statements for processing each element of salaries | for (float f:salaries)
Suppose the declared type of x is a class, and the declared type of y is an interface. When is the assignment x = y; legal | when the...x is object
Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment xarr = yarr; legal | sometimes
Suppose x and y are of type TrafficLightState, which is an enum. What is the best way to test whether x and y refer to the same constant | if (x == y)
Suppose you are writing a class that will provide custom deserialization. What access mode should the readObject() method have | private
Suppose you are writing a class that will provide custom serialization. What access mode should the writeObject() method have | private
Suppose you want to create a custom thread class by extending java.lang.Thread in order to provide some special functionality | override run()
Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions. You decide to subclass java.lang.Math and provide the new functionality as a set of static methods | subclass java.lang.math
Swing components cannot be combined with AWT components | true
class is the primary class that has the driver information | drivermanager
class is used to implement a pull-down menu that provides a number of items to select from | menu
The element method alters the contents of a Queue | false
The Swing component classes can be found in the | javax.swing
There are two classes in Java to enable communication using datagrams namely | datapacket and datasocket
Compilation of Parrot.java fails at line 7 because method getRefCount() is static in the superclass, and static methods may not be overridden to be nonstatic | dai nhat: nonstatic
Compilation of Nightingale will succeed, but an exception will be thrown at line 10, because method fly() is protected in the superclass | the program...after: 2
void doSomething() throws IOException, EOFException | ngan-dai nhat, throws eofexception
URL referring to databases use the form | protocol:subprotocol:datasoursename
What are the legal types for whatsMyType | there are no possible legal types
What does the following code do | throws an exception
There is no output because the code throws an exception at line 1 | output is i = 20
1000 | -1
What happens when you try to compile and run the following application | thrown at line 9
The code compiles, and prints out >>null<< | out >>null<<
An exception is thrown at line 6 | thrown at line 7
What is -50 >> 2 | -13
What is 7 % -4 | 3
What is -8 % 5 | -3
What is the difference between the rules for method-call conversion and the rules for assignment conversion | there is no difference
The code will compile as is. No modification is needed | on line 1, remove
What is the range of values that can be assigned to a variable of type byte | ?2mu7 through 2mu7 ? 1
What is the range of values that can be assigned to a variable of type short | ?2mu15 through
The code compiles and executes; afterward, the current working directory contains a file called datafile | the code fails to compile
What is the return type of the instanceof operator | a boolean
What method of the java.io.File class can create a file on the hard drive | createnewfile()
The output: value is 99.99 | value is 9.0
The output: b contains 250 | b contains 5
What would be the output from this code fragment | message four
When a byte is added to a char, what is the type of the result | int
When a negative byte is cast to a long, what are the possible values of the result | negative
When a negative long is cast to a byte, what are the possible values of the result | all the above
When a short is added to a float, what is the type of the result | float
When comparing java.io.BufferedWriter to java.io.FileWriter, which capability exists as a method in only one of the two | writing a line
When does an exception's stack trace get recorded in the exception object | is constructed
When is it appropriate to pass a cause to an exception's constructor | in response to catching
When is it appropriate to write code that constructs and throws an error | never
When is x & y an int | sometimes
When the user attempts to close the frame window, _______ event in generated | window closing
When the user selects a menu item, _______ event is generated | action event
Java programming language, the compiler converts the human-readable source file into platform-independent code that a Java Virtual Machine can understand | bytecode
Whenever a method does not want to handle exceptions using the try block, the | throws
Which are the correct statements used for getting connection object to connect to SQL Server database | string url =jdbc:odbc
Which class and static method can you use to convert an array to a List | arrays.aslist
Which is four-step approach to help you organize your GUI thinking | identify, isolate, sketch
Which is the four steps are used in working with JDBC | connect, create, look
Which JDBC processing model  that requires a JDBC driver that can communicate with the particular data source being accessed | two-tier
Which line of code tells a scanner called sc to use a single digit as a delimiter | sc.usedelimiter("\\d")
Man has the best friend who is a Dog | private dog bestfriend
Which methods return an enum constant’s name | 2.name(), tostring()
Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class's persistent state | transient
Which of the following are legal argument types for a switch statement | 3.byte, int, char
Which of the following are legal enums | 3.ngan-dai nhat, lion int weight
Which of the following are legal import statements | 2.import...vector, vector.*
Which of the following are legal loop constructions | for (int k=0, j+k != 10; j++,k++)
Which of the following are legal loop definitions | none of the above
double d = 1.2d5 | 2.double d = 1.2d, 1.2d
int d = 0XABCD | 2.int c = 0xabcd, dai nhat
char c = 0x1234 | 2.0x.., '\u1234'
Vector <String> theVec = new Vector<String>() | 2.list...<string>(), dai nhat
Which of the following are methods of the java.util.SortedMap interface | headmap, tailmap, submap
Which of the following are methods of the java.util.SortedSet interface | all the above
System.out has a println() method | all the above
The JVM runs until there is only one non-daemon thread | are no non-daemon
When an application begins running, there is one non-daemon thread, whose job is to execute main() | 3.nhat, thread, non-daemon thread
When you declare a block of code inside a method to be synchronized, you can specify the object on whose lock the block should synchronize | 2.the method always, nhat
An enum definition should declare that it extends java.lang.Enum | 2.contain public, private
Primitives are passed by reference | 2.by value
An anonymous inner class that implements several interfaces may extend a parent class other than Object | implement at most, class may extend
Which of the following are valid arguments to the DataInputStream constructor | fileinputstream
Which of the following are valid mode strings for the RandomAccessFile constructor | all the above
Which of the following calls may be made from a non-static synchronized method | all the above
Which of the following classes implement java.util.List | 2.arraylist, stack
Which of the following classes implements a FIFO Queue | linkedlist
Which of the following declarations are illegal | 3.ngan-dai nhat, double d
int x = 6; if (!(x > 3)) | 2.dai nhat, x = ~x
String x = "Hello"; int y = 9; if (x == y) | 2.ngan nhat, x=x+y
Which of the following expressions results in a positive value in x | int x = –1; x = x >>> 5
Which of the following interfaces does not allow duplicate objects | set
Which of the following is not appropriate situations for assertions | preconditions of a public method
Which of the following is NOTa valid comment | /* comment
Which of the following is the most appropriate way to handle invalid arguments in a public method | illegalargumentexception
Readers have methods that can read and return floats and doubles | none of the above
An enum definition may contain the main() method of an application | all the above
Which of the following may appear on the left-hand side of an instanceof operator | a reference
Which of the following may appear on the right-hand side of an instanceof operator | 2.a class, an interface
Which of the following may be declared final | 2.classes, methods
Which of the following may be statically imported | 2.static method, static field
Which of the following may follow the static keyword | 3.data, methods, code blocks
Which of the following may legally appear as the new type (between the parentheses) in a cast operation | all of
Which of the following may not be synchronized | classes
Which of the following may override a method whose signature is void xyz(float f) | 2.void, public void xyz(float f)
Which of the following methods in the Thread class are deprecated | suspend() and resume()
Which of the following operations might throw an ArithmeticException | none of
Which of the following operators can perform promotion on their operands | 3.cong, tru, xap xi
Which of the following restrictions apply to anonymous inner classes | must be defined
Which of the following should always be caught | checked exceptions
Which of the following signatures are valid for the main() method entry point of an application | 2.static void...(string arg[])
Which of the following statements about the wait() and notify() methods is true | calls wait() goes into
Which of the following statements about threads is true | threads inherit their
A final class may not contain non-final data fields | may not be extended
An abstract class must declare that it implements an interface | none
An abstract class may not have any final methods | only statement 2
Only object references are converted automatically; to change the type of a primitive, you have to do a cast | both primitives
Transient methods may not be overridden | variables are not
Object references can be converted in both method calls and assignments, but the rules governing these conversions are very different | conversions are identical
Bytecode characters are all 16 bits | unicode characters
To change the current working directory, call the changeWorkingDirectory() method of the File class | none
When you construct an instance of File, if you do not use the file-naming semantics of the local machine, the constructor will throw an IOException | none
When the application is run, thread hp1 will execute to completion, thread hp2 will execute to completion, then thread hp3 will execute to completion | none of
Compilation succeeds, although the import on line 1 is not necessary. During execution, an exception is thrown at line 3 | fails at line 2
Compilation fails at line 1 because the String constructor must be called explicitly | succeeds. no exception
Line 4 executes and line 6 does not | line 6 executes
There will be a compiler error, because class Greebo does not correctly implement the Runnable interface | runnable interface
The acceptable types for the variable j, as the argument to the switch() construct, could be any of byte, short, int, or long | value is three
The returned value varies depending on the argument | returns 0
Lines 5 and 12 will not compile because the method names and return types are missing | output x = 3
Line 13 will not compile because it is a static reference to a private variable | output is x = 104
Which statements about JDBC are NOT true | 2.database system, dbms
Which two code fragments correctly create and initialize a static array  of int elements | 2.a = { 100,200 }, static
Which two of the following interfaces are at the top of the hierarchies in the Java Collections Framework | 2.map, collection
A new directory called dirname and a new file called filename are created, both in the current working directory | no directory
protected class Cat extends Owner | public class cat extends pet
Date vaccinationDue | 2.boolean, string
What is -15 % -10 | -5
command line on a Windows  system | 2.must contain  the statement, the file
The string created on line 2 does not become eligible for garbage collection in this code | after line 3
When the application runs, what are the values of n and w.x after the call to bump()  in the main | n is 10, w.x  is 11
The addAll() method  of that  interface  takes a single argument, which is a reference to a collection whose elements are compatible with E. What  is the declaration of the addAll() method | addall(collection<? extends e> c)
If you want a vector in which you know you will only store strings, what are the advantages of using fancyVec rather than plainVec | attempting to...compiler error
When should objects stored in a Set implement  the java.util.Comparable interface | set is a treeset
What relationship does the extends keyword  represent | is a
class bbb.Bbb, which extends aaa.AAA, wants to override callMe(). Which access modes for callMe() in aaa.AAA will allow this | 2.public, protected
Lemon lem  = new Lemon(); Citrus cit = new Citrus() | 3.cit = lem, cit=(citrus), lem=(lemon)
it also has a method  called chopWoodAndCarryWater(), which just calls the other two methods | inappropriate cohesion, inappropriate coupling
sharedOb.wait() | 2.athread.interrupt, sharedob.notifyall
line prints double d in a left-justified field that is 20 characters wide, with 15 characters to the right of the decimal point | system.out.format("%-20.15f", d)
What code at line 3 produces  the following output | string  delim =  “\\d+”
How do you generate a string representing  the value of a float f in a format  appropriate for a locale loc | numberformat.getinstance(loc)
you want to use a DateFormat to format  an instance of Date.  What factors influence the string returned by DateFormat’s format() method | 2.long, or full, the locale
you want to create a class that compiles and can be serialized and deserialized without causing an exception  to be thrown. Which statements  are true regarding  the class | 2.dai nhat, ngan nhat
you are writing a class that will provide custom deserialization. The class implements java.io.Serializable (not java.io.Externalizable) | private
What interfaces can be implemented in order to create a class that can be serialized | 2.dai nhat, ngan nhat
The file contains  lines of 8-bit text, and the 8-bit encoding represents the local character set, as represented by the cur- rent default locale. The lines are separated by newline characters | filereader instance
shorty is a short and wrapped is a Short | all
How is IllegalArgumentException used | 2.certain methods, public methods
While testing some code that you are developing,  you notice that an ArrayIndexOutOf- BoundsException is thrown. What is the appropriate reaction | none
Which lines check that x is equal to four? Assume assertions  are enabled at compile time and runtime | 2.assert x  == 4
int[]  ages = {  9, 41, 49  }; int sum = 0 | 2.i<ages.length, for (int i:ages)
Which of the following types are legal arguments  of a switch statement | enums, bytes
class A  extends java.util.Vector  { private  A(int x) | does not create a default
void  callMe(String… names) | method,  names is an array
Given a class with a public variable theTint of type Color, which of the following methods are consistent  with the JavaBeans naming standards | public color getthetint()
are valid arguments  to the DataInputStream constructor | fileinputstream
are valid mode strings for the RandomAccessFile constructor | r, rw, rws, rwd
method  of the java.io.File class can create a file on the hard drive | createnewfile()
class A extends Object; Class B extends A; and class C extends B. Of these, only class C implements java.io.Externalizable | c must have
class A extends Object; class B extends A; and class C extends B. Of these, only class C implements java.io.Serializable | b must have
you are writing a class that will provide custom serialization. The class implements java.io.Serializable (not java.io.Externalizable) | private
How do you use the File class to list the contents  of a directory | string[]  contents =  myfile.list();
call returns  true if a1 and a2 have the same length, and a1[i].equals(a2[i]) for every legal index i | java.util.arrays.equals(a1, a2)
line of code tells a scanner called sc to use a single digit as a delimiter | sc.usedelimiter(“\\d”)
you want to write a class that offers static methods to compute hyperbolic trigonometric functions.  You decide to subclass java.lang.Math and provide the new functionality as a set of static methods | java.lang.math
Given a string constructed by calling s = new String(“xyzzy”), which of the calls modifies the string | none
Suppose you want to create a custom thread  class by extending  java.lang.Thread in order to provide some special functionality. Which of the following must you do | override  run()
you prevent shared data from being corrupted in a multithreaded environment | access the variables
Is it possible to write code that can execute only if the current  thread  owns multiple locks | yes
statements  about  the wait() and notify() methods  is true | pool of waiting threads
methods  in the Thread class are deprecated | suspend() and resume()
A Java monitor must either extend Thread or implement  Runnable | false
One of the threads  is thr1. How can you notify thr1 so that it alone moves from the Waiting state to the Ready state | you cannot  specify
A thread  wants to make a second thread  ineligible for execution.  To do this, the first thread  can call the yield() method  on the second thread | false
Which methods  return  an enum constant’s  name | name(), tostring()
restrictions apply to anonymous inner classes | inside a code block
A pet has an owner,  a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating whether  it has been neutered,  and a textual  description  of its markings | boolean, string
Which of the following are valid declarations? Assume java.util | 1vector 2set 3map string,string
You can determine  all the keys in a Map in which of the following ways | set object from the map
What keyword  is used to prevent an object from being serialized | transient
abstract class can contain  methods  with declared bodies. | public, protected, default,  private
access modifier allows you to access method  calls in libraries not created in Java | native
Which of the following statements  are true? (Select all that apply.) | object cannot reassigned
The keyword  extends refers to what type of relationship | is a
keywords  is used to invoke a method  in the parent  class | super
What is the value of x after the following operation is performed | 3
method  call is used to tell a thread  that it has the opportunity | notify()
Assertions are used to enforce all but which | exceptions
force garbage collection by calling System.gc(). | false
Select the valid primitive data type | 1.boolean 2.char 3.float
How many bits does a float contain | 32
What is the value of x after the following line is executed | 32
StringBuffer is slower than a StringBuilder, but a StringBuffer | true
list of primitives ordered  in smallest to largest bit size representation | char, int, float, long
Which class provides locale-sensitive text formatting for date and time information | java.text.dateformat
int x  = 9; byte b  = x | false
Which of the following code snippets compile | 1.integer 2.integer 3.byte
Java arrays always start at index 1 | false
accurately  describes how variables are passed to methods | that are primitive type are passed by value
change the value that  is encapsulated by a wrapper class after you have instan | none of the above.
The class implements java.io.Serializable (and not java.io.Externalizable) | private  readobject
A signed data type has an equal number  of non-zero  positive and negative values | false
signatures are valid for the main() method entry point of an application | public static  void main(string[] args)
three top-level elements occur in a source file, they must appear | package declaration, imports,  class/interface/enum definitions
int[] x  = new int[25] | x[24] is 0 and x.length is 25
How can you force garbage collection of an object | garbage  collection cannot  be forced.
range of values that can be assigned to a variable of type short | -215  through 215   - 1
range of values that can be assigned to a variable of type byte | -27  through 27  - 1
How do the imports  affect the time required  to compile the source file | compilation takes slightly more time
How do the imports  affect the time required  to load the class? | class loading takes no additional time
legal import statements | 1.import  java.util.vector    2.import  static java.util.vector
may be statically imported | 1.static method  names 2.static field names
int c  =  0xabcd and int d  =  0XABCD | 2 dap an
double d  =  1.2d and double d  =  1.2D | 2 dap an
char c  =  ‘\u1234’ | 1 dap an
passed by value and passed by value | 2 dap an
int x  =  6; if (!(x >  3)) and int x  =  6; x  =  ~x | 2 dap an
int x  =  –1; x  =  x  >>> 5 | 1 dap an
int y  =  9; x  += y; and int y  =  9; x  =  x  +  y; | 2 dap an
What is 7 % -4? | 3
ob1 == ob2 | no
When a byte is added to a char | int
When a short is added to a float | float
ArithmeticException | 1.none of these      2./
What is the return  type of the instanceof operator | boolean
may appear on the left-hand  side of an instanceof operator | reference
may appear on the right-hand side of an instanceof operator | class and interface
What is -50  >>  1 | -25
default String s ,, abstract  double d ,, double hyperbolic | 3 dap an
A final class may not have any abstract methods | true
denote a variable that should not be written out as part of its class’s persistent  state | transient
Both primitives and object references can be both converted  and cast | dap an
and the rules governing these conversions  are identical | dap an
may legally appear  as the new type (between the parentheses)  in a cast operation | all of the above
type of x is a class, and the declared type of y is an interface. When is the assignment  x  =  y | when the type of x is object
xarr is an array of XXX, and the type of yarr is an array of YYY | sometimes
When is x  &   y an int | sometimes
negative long is cast to a byte | all of the above
negative byte is cast to a long | negative
operators can perform  promotion on their operands | + - ~(nga)
difference between the rules for method-call conversion and the rules for assignment conversion | there is no difference
Which of the following are appropriate situations for assertions | dap an sai : preconditions of a public method
appropriate way to handle invalid arguments  in a public method | illegalargumentexception
Suppose salaries is an array containing  floats | for (float f:salaries)
Suppose a method  called finallyTest() consists of a try block | if the jvm doesn’t crash and
appropriate to pass a cause to an exception’s constructor | thrown in response to catching of a different exception  type
When does an exception’s stack trace get recorded  in the exception  object | is constructed

the string? | none of the above
Which one statement is true about the following code? | if (s1 == s2)
static methods. Which one statement is true about this strategy? | the strategy fails because you cannot subclass java.lang.math.
Which one statement is true about the following code fragment? | compilation fails at line 2.
E Which one statement is true about the following code fragment? | if (s1.equals(s))
2. sbuf.insert(3, "xyz"); | a.true
2. sbuf.append("xyz"); | a.true
4. System.out.println("Line 4"); | a.true
4. System.out.println("Line 4"); | b. false
D.wrapped = 9; | abcd
BD Which of the following are legal? (Choose all that apply.) | list<string> thelist = new vector<string>(); vector <string> thevec = new vector<string>();
which of the following are legal? (Choose all that apply.) | a.iterator<string> iter = names.iterator(); b. for (string s:names)
Which of the following are legal clone()methods in a class called Q13that extends Object? | public object clone()
Which of the following classes implement java.util.List? | a.java.util.arraylist d.java.util.stack
E. subSet | all
E. subMap | cde
F. sc.useDelimiter("\\d+"); | c
10. } | 7
a1[i].equals(a2[i])for every legal index i? | a.java.util.arrays.equals(a1, a2);
AD Which of the following statements are true? | a.stringbuilderis generally faster than stringbuffer. d.stringbufferis threadsafe;stringbuilderis not.
creating an object with the "new" operator, eg. str1 = new String("hello"); | instantiation
a description of a possible object | class
identity, state, behavior | three main characteristics of objects
a section of memory that contains both variables (state information) and methods (small programs) | object
a characteristic of a class definition that is not shared by its objects ("no matter how many objects are made, there will be only one of these") | static
the "new" operator is used with a _____ to create an object | constructor
used when an object is created | class description
accesses members (variables and methods) of an object, eg. len = str1.length(); | dot notation
allow you to use prewritten code/classes/toolkits/packages | library classes
attributes/variables that define the object's state; can hold numbers, characters, strings, other objects | field
actions that an object can take (behaviors) | methods
can be called only from constructors or methods of the same class | private methods
can be called from constructors or methods of any class | public methods
the ability to extend an existing type of objects, by adding new fields and methods, and/or overriding some of the methods | inheritance
hiding information from unwanted outside access and attaching that information only to methods that need access to it | encapsulation
It is a non-static field (dynamic variable). The values are unique to each instance of a class. Ex: the current speed of one bicycle is independent of the current speed of another. | define: instance variable
It is a static variable. There is only one copy of this variable no matter how many times a class has been initiated. Ex: Number of gears in a bicycle that doesn't differ within a class | define: class variable
Keyword: Final (used to indicate that the variable (number) will never change) | what modifier and keyword are used to declare a class variable.
Variable declared within a method that stores the temporary state of a variable. (Only visible to the methods they are declared in and not accessible from rest of the class) | define: local variable
variables that define ex: args | parameters
If variable is constant, use capitals. Ex: BigPinkBear | rules for naming
byte, short, into, long, float, double, boolean, char | what are the 8 primitive data types?
integer with min value of -128 and max value of +127(inclusive) 8 bit (for memory saving) | byte
integer with min value of -32,768 and max value of +32,767(inclusive) 16 bit (for memory saving) | short
integer 32 bit, big enough for most operations (2million) - default choice | int
integer 64 bit, (9 million) | long
32 bit decimal value - do not use for precise values | float
64 bit decimal value - do not use for precise values | double
Can only have two values - true/false | boolean
16 bit Unicode character | char
java.lang.String | character string class is represented by?
Objects have two properties. One is state. What is the other? | behavior
The behavior of an object is represented by ______ ______ | instance methods
The job of a _____ is to initialize instance variables at the time an object is created. | constructor
Nested inside a class declaration are three kinds of declarations. What are they? | constructor declarations
The words public and private are _____ _____ | access modifiers
A method is allowed to have _______, which represent data that will be supplied when the method is called. | parameters
Once a class has been declared, we can create objects that belong to the class. We say that these objects are ______ of the class. | instances
An object variable doesn't actually store an object. Instead, it stores a ______ to an object. | reference
The keyword ______ is placed before a class name in order to create an object. | new
To perform an operation on an object, we _______ one of the instance methods associated with the object. | call
How do you call an instance method | object.methodname(arguments)
Reference variables are known as _______ variables in other programming languages | pointer
What value can we assign to an object variable to indicate that it doesn't currently store an object? | null
A new object that's been created by copying an existing object is said to be a _______. | clone
An object that's no longer accessible through any object variable is said to be _______. | garbage
An instance method that returns the value of an instance variable is said to be an _______. | accessor/getter
An instance method that stores its parameter into an instance variable is said to be an ________. | mutator/setter
An object whose instance variables cannot be changed is said to be _______. | immutable
A mehtod that returns the contents of an object as a string should be named ______. | tostring
The act of joining two strings together to form a single string is called _______. | concatenation
Which method is used to remove extra space from the beginning and end of a string? | trim
What is the value of 11 + 38 + "THX"? | 49thx
is a set of java API  for executing SQL statements | jdbc
There are a number of situations in software engineering when it is important for disparate groups of programmers to agree to a "contract" that spells out how their software ____. Each group should be able to write their code without any _____ of how the other group's code is written. Generally speaking, _____ are such contracts. | interacts, interfaces, knowledge
The auto manufacturers must publish an industry-standard ____ that spells out in detail what _____ can be invoked to make the car move (any car, from any manufacturer). | interface, methods
In the Java programming language, an interface is a _____ type, similar to a ____, that can contain only constants, method signatures, and nested types | reference, class
} | constants, method signatures, nested types
Can interfaces be instantiated? | no
Can classes be instantiated? | yes
Interfaces cannot be instantiated—they can only be ________ by classes or ______ by interfaces. | implemented, extended
Interfaces cannot be instantiated—they can only be implemented by _____ or extended by ______. | classes, interfaces
Fill the blank with a method signature of function1. | int turn(int intiger1);
make a public interface called Hello: | public interface hello {}
Fill the blank with a method signature of function1. | function1
Write a public class "Class1" that implements the interface "InterfaceGo" | public class class1 implements interfacego{}
Write a private class "GoClass" that implements the interface "InterfaceForClass" | private class goclass implements interfaceforclass{}
The robotic car example shows an interface being used as an industry standard _______ | application programming interface
A company calls SoftwareFactory makes a package of digital image processing ____ that are sold to companies making ____ graphics programs (Adobe). The image processing company (SoftwareFactory) writes its classes to implement an ____, which it makes public to it's costumers. Adobe then invokes the image processing methods using the signatures and return types defined in the interface. While the SoftwareFactory's API is made public (to its customers), its implementation of the API is kept as a closely guarded secret—in fact, it may revise the implementation at a later date as long as it continues to implement the original interface that its customers have relied on. | methods, end-user, interface
Consider the following application:1. class Q7 {2. public static void main(String args[]) {3. double d = 12.3;4. Decrementer dec = new Decrementer();5. dec.decrement(d);6. System.out.println(d);7. }8. } 9.10. class Decrementer {11. public void decrement(double decMe) 12. decMe = decMe - 1.0;13. }14. }What value is printed out at line 6? | 12.3
Which of the following are legal? | char c = '\u1234';
Consider the following code:1. StringBuffer sbuf = new StringBuffer();2. sbuf = null;3. System.gc();Choose all true statements: | after line 2 executes, the stringbuffer object is eligible for garbage collection.
Which of the following expressions results in a positive value in x? | int x = -1; x = x >>> 5;
Suppose ob1 and ob2 are references to instances of java.lang.Object. If (ob1 == ob2) is false, can ob1.equals(ob2) ever be true? | no
Which of the following operations might throw an ArithmeticException? | none of these
Which of the following operations might throw an ArithmeticException? | /
Which of the following may appear on the left-hand side of an instanceof operator? | a reference
Which of the following may appear on the right-hand side of an instanceof operator? (Choose all that apply.) | a class vs an interface
What is -50 >> 1? | -25
What is the minimal modification that will make this code compile correctly?1. final class Aaa2. {3. int xxx;4. void yyy() { xxx = 1; }5. } 6.7.8. class Bbb extends Aaa9. {10. final Aaa finalref = new Aaa(); 11.12. final void yyy()13. {14. System.out.println("In method yyy()");15. finalref.xxx = 12345;16. }17. } | on line 1, remove the final modifier.
Which of the following statements is true? | transient variables are not serialized.
Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class's persistent state? (Choose the shortest possible answer.) | transient
This question concerns the following class definition:1. package abcde; 2.3. public class Bird {4. protected static int referenceCount = 0;5. public Bird() { referenceCount++; }6. protected void fly() { / Flap wings, etc. / }7. static int getRefCount() { return referenceCount; }8. }Which statement is true about class Bird and the following class Parrot?1. package abcde; 2.3. class Parrot extends abcde.Bird {4. public void fly() {5. / Parrot-specific flight code. /6. }7. public int getRefCount() {8. return referenceCount;9. }10. } | compilation of parrot.java fails at line 7 because method getrefcount() is static in the superclass, and static methods may not be overridden to be nonstatic.
1. package singers; 2.3. class Nightingale extends abcde.Bird {4. Nightingale() { referenceCount++; } 5.6. public static void main(String args[]) {7. System.out.print("Before: " + referenceCount);8. Nightingale florence = new Nightingale();9. System.out.println(" After: " + referenceCount);10. florence.fly();11. }12. } | the program will compile and execute. the output will be before: 0 after: 2.
Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides doSomething(). What access modes may Subby's version of the method have? (Choose all that apply.) | public vs protected
Which of the following statements are true? | none of the above.
Inty but does not provide implementations for any of the five interface methods. Which is/are true? | the class will compile if it is declared abstract vs the class may not be instantiated.
Which of the following may be declared final? (Choose all that apply.) | classesvsdatavsmethods
Which of the following may follow the static keyword? (Choose all that apply.) | datavsmethodsvscode blocks enclosed in curly brackets
Suppose class A has a method called doSomething(), with default access. Suppose class B extends A and overrides doSomething(). Which access modes may apply to B's version of doSomething()? (Choose all that apply.) | publicvsprotectedvsdefault
True or false: If class Y extends class X, the two classes are in different packages, and class X has a protected method called abby(), then any instance of Y may call the abby() method of any other instance of Y. | false
Which of the following statements are true?1 | a final class may not be extended.
Which of the following statements is correct? (Choose one.) | both primitives and object references can be both converted and cast.
Consider the following class:1. class Cruncher {2. void crunch(int i) {3. System.out.println("int version");4. }5. void crunch(String s) {6. System.out.println("String version");7. } 8.9. public static void main(String args[]) {10. Cruncher crun = new Cruncher();11. char ch = 'p';12. crun.crunch(ch);13. }14. }Which of the following statements is true? (Choose one.) | the code will compile and produce the following output: int version.
Which of the following statements is true? (Choose one.) | object references can be converted in both method calls and assignments, and the rules governing these conversions are identical.
Consider the following code. Which line will not compile?1. Object ob = new Object();2. String[] stringarr = new String[50];3. Float floater = new Float(3.14f);4. ob = stringarr;5. ob = stringarr[5];6. floater = ob;7. ob = floater; | line 6
Consider the following code:1. Cat sunflower;2. Washer wawa;3. SwampThing pogo; 4.5. sunflower = new Cat();6. wawa = sunflower;7. pogo = (SwampThing)wawa;Which of the following statements is true? (Choose one.) | the code will compile but will throw an exception at line 7, because the runtime class of wawa cannot be converted to type swampthing.
Consider the following code:1. Raccoon rocky;2. SwampThing pogo;3. Washer w; 4.5. rocky = new Raccoon();6. w = rocky;7. pogo = w;Which of the following statements is true? (Choose one.) | line 7 will not compile; an explicit cast is required to convert a washer to a swampthing.
Which of the following may legally appear as the new type (between the parentheses) in a cast operation? | all of the above
Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment xarr = yarr; legal? | sometimes
When is x & y an int? (Choose one). | sometimes
What are the legal types for whatsMyType? short s = 10; whatsMyType = !s; | there are no possible legal types.
When a negative long is cast to a byte, what are the possible values of the result? | all of the above
What is the difference between the rules for method-call conversion and the rules for assignment conversion? | there is no difference; the rules are the same.
Consider the following code:1. outer: for (int i = 0; i < 2; i++) {2. for (int j = 0; j < 3; j++) {3. if (i == j) {4. continue outer;5. }6. System.out.println("i = " + i + " j = " + j);7. }8. }Which lines would be part of the output? (Choose all that apply.) | i = 1 j = 0
Which of the following are legal loop constructions? (Choose all that apply.) | int j = 0;for (int k=0, j+k != 10; j++,k++) { system.out.println("j=" + j + ", k=" + k);}
What would be the output from this code fragment?1. int x = 0, y = 4, z = 5;2. if (x > 2) {3. if (y < 5) {4. System.out.println("message one");5. }6. else {7. System.out.println("message two");8. }9. }10. else if (z > 5) {11. System.out.println("message three");12. }13. else {14. System.out.println("message four");15. } | message four
Which statement is true about the following code fragment?1. int j = 2;2. switch (j) {3. case 2:4. System.out.println("value is two");5. case 2 + 1:6. System.out.println("value is three");7. break;8. default:9. System.out.println("value is " + j);10. break;11. } | the output would be the text value is two followed by the text value is three.
Which of the following are legal argument types for a switch statement? | bytevsintvschar
When is it appropriate to pass a cause to an exception's constructor? | when the exception is being thrown in response to catching of a different exception type
Which of the following should always be caught? | checked exceptions
When does an exception's stack trace get recorded in the exception object? | when the exception is constructed
When is it appropriate to write code that constructs and throws an error? | never
Consider the following classes, declared in separate source files:1. public class Base {2. public void method(int i) {3. System.out.print("Value is " + i);4. }5. }1. public class Sub extends Base {2. public void method(int j) {3. System.out.print("This value is " + j);4. }5. public void method(String s) {6. System.out.print("I was passed " + s);7. }8. public static void main(String args[]) {9. Base b1 = new Base();10. Base b2 = new Sub();11. b1.method(5);12. b2.method(6);13. }14. }What output results when the main method of the class Sub is run? | consider the following classes, declared in separate source files:1. public class base {2. public void method(int i) {3. system.out.print("value is " + i);4. }5. }1. public class sub extends base {2. public void method(int j) {3. system.out.print("this value is " + j);4. }5. public void method(string s) {6. system.out.print("i was passed " + s);7. }8. public static void main(string args[]) {9. base b1 = new base();10. base b2 = new sub();11. b1.method(5);12. b2.method(6);13. }14. }what output results when the main method of the class sub is run?  |  Consider the following classes, declared in separate source files:
1. public class Base {2. public void method(int i) {3. System.out.print("Value is " + i);4. }5. }1. public class Sub extends Base {2. public void method(int j) {3. System.out.print("This value is " + j);4. }5. public void method(String s) {6. System.out.print("I was passed " + s);7. }8. public static void main(String args[]) {9. Base b1 = new Base();10. Base b2 = new Sub();11. b1.method(5);12. b2.method(6);13. }14. }What output results when the main method of the class Sub is run? | value is 5this value is 6
Consider the following class definition:1. public class Test extends Base {2. public Test(int j) {3. }4. public Test(int j, int k) {5. super(j, k);6. }7. }Which of the following forms of constructor must exist explicitly in the definition of the Baseclass? Assume Test and Base are in the same package. (Choose all that apply.) | base() { }vsbase(int j, int k) { }
Which of the following statements are true? (Choose all that apply.) | given that inner is a nonstatic class declared inside a public class outer and that appro- priate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
Which of the following may override a method whose signature is void xyz(float f)? | void xyz(float f)vspublic void xyz(float f)
Suppose x and y are of type TrafficLightState, which is an enum. What is the best way to test whether x and y refer to the same constant? | if (x == y)
Which of the following restrictions apply to anonymous inner classes? | they must be defined inside a code block.
Which methods return an enum constant's name? | name()vstostring()
Which of the following methods may appear in class Y, which extends X? | void dosomething(int a, float b) { ... }
16. } | there will be a compiler error, because class greebo does not correctly implement the
20. } | when the application is run, all three threads (hp1, hp2, and hp3) will execute concurrently, taking time-sliced turns in the cpu.
13. } | yes
A Java monitor must either extend Thread or implement Runnable. | false
Which of the following methods in the Thread class are deprecated? | suspend() and resume()
Which of the following statements about threads is true? | threads inherit their priority from their parent thread.
Which of the following statements about the wait() and notify() methods is true? | the thread that calls wait() goes into the monitor's pool of waiting threads
How many locks does an object have? | one
Is it possible to write code that can execute only if the current thread owns multiple locks? | yes.
How do you prevent shared data from being corrupted in a multithreaded environment? | access the variables only via synchronized methods.
How can you ensure that multithreaded code does not deadlock? | a, b, and c do not ensure that multithreaded code does not deadlock.
Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions. You decide to subclass java.lang.Math and provide the new functionality as a set of static methods. Which one statement is true about this strategy? | the strategy fails because you cannot subclass java.lang.math.
4. myMath.cos(0.123)); | compilation fails at line 2.
6. s = null; | compilation succeeds. no exception is thrown during execution.
2. sbuf.insert(3, "xyz"); | true
2. sbuf.append("xyz"); | true
4. System.out.println("Line 4"); | true
4. System.out.println("Line 4"); | false
Which of the following are legal? (Choose all that apply.) | list<string> thelist = new vector<string>();vector <string> thevec = new vector<string>();
Which of the following classes implement java.util.List? | java.util.arraylistvsjava.util.stack
Which line of code tells a scanner called sc to use a single digit as a delimiter? | sc.usedelimiter("\\d");
Which of the following statements are true? | stringbuilder is generally faster than stringbuffer.vsstringbuffer is threadsafe; stringbuilder is not.
Which of the statements below are true? (Choose all that apply.) | unicode characters are all 16 bits.
Which of the statements below are true? (Choose all that apply.) | none of the above.
9. catch (IOException e) { } | 12
2. File f2 = new File(f1, "filename"); | no directory is created, and no file is created.
13. catch (IOException e) { } | the code fails to compile.
Suppose you are writing a class that will provide custom serialization. The class implements java.io.Serializable (not java.io.Externalizable). What access mode should the writeObject() method have? | private
Suppose you are writing a class that will provide custom deserialization. The class implements java.io.Serializable (not java.io.Externalizable). What access mode should the readObject() method have? | private
Suppose class A extends Object; class B extends A; and class C extends B. Of these, only class C implements java.io.Serializable. Which of the following must be true in order to avoid an exception during deserialization of an instance of C? | b must have a no-args constructor.
Suppose class A extends Object; Class B extends A; and class C extends B. Of these, only class C implements java.io.Externalizable. Which of the following must be true in order to avoid an exception during deserialization of an instance of C? | c must have a no-args constructor.
What method of the java.io.File class can create a file on the hard drive? | createnewfile()
15. } | an exception is thrown at line 9.
Given a class with a public variable theTint of type Color, which of the following methods are consistent with the JavaBeans naming standards? | public color getthetint()
void callMe(String... names) { } | within the method, names is an array containing strings.
Which statements are true? | the compiler does not create a default constructor.
Which of the following types are legal arguments of a switch statement? | enumsvsbytes
Which of the following are legal ways to add the elements of the array? | for (int i=0; i<ages.length; i++) sum += ages[i];vsfor (int i:ages) sum += i;
Which lines check that x is equal to four? Assume assertions are enabled at compile time and runtime. | assert x == 4;vsassert x == 4 : "x is not 4";
} | object streamvsfinally
While testing some code that you are developing, you notice that an ArrayIndexOutOf- BoundsException is thrown. What is the appropriate reaction? | none of the above.
Suppose you want to use a DateFormat to format an instance of Date. What factors influence the string returned by DateFormat's format() method? | the style, which is one of short, medium, long, or fullvsthe locale
How do you generate a string representing the value of a float f in a format appropriate for a locale loc? | numberformat nf = numberformat.getinstance(loc); string s = nf.format(f);
aeiou AEIOU | string delim = "\\d+";
Which line prints double d in a left-justified field that is 20 characters wide, with 15 characters to the right of the decimal point? | system.out.format("%-20.15f", d);
} | the code prints "going to sleep," then "waking up," and then "all done."
} | class zebra generates a compiler error
What code at line 4 results in a class that compiles? | super();vsthis(1.23f);
What relationship does the extends keyword represent? | "is a"
When should objects stored in a Set implement the java.util.Comparable interface? | when the set is a treeset
Which methods below honor the hash code contract? | public int hashcode() { return a; }vs public int hashcode() { return (int)math.random();}
Give the following declarations: Vector plainVec; Vector<String> fancyVec;If you want a vector in which you know you will only store strings, what are the advantages of using fancyVec rather than plainVec? | attempting to add anything other than a string to fancyvec results in a compiler error.
The addAll() method of that interface takes a single argument, which is a reference to a collection whose elements are compatible with E. What is the declaration of the addAll() method? | public boolean addall(collection<? extends e> c)
Which of the following may appear in a subclass of Fish named Tuna that is not in the ocean package? | public void swim() { }vssize = 12;
main() method? | n is 10, w.x is 11
5. t = null; | after line 3
What is -15 % -10? | -5
method is used to wait for a client to initiate communications. | accept()
What is the result? (Choose one.) | line 26 prints "a" to system.out.
C? (Choose two.) | the code on line 29 will be executed.vsthe exception will be propagated back to line 27.
What is the result? (Choose one.) | an exception is thrown at runtime.
What is the result? (Choose one.) | third second first snootchy 420
A monitor called mon has 10 threads in its waiting pool; all these waiting threads have the same priority. One of the threads is thr1. How can you notify thr1 so that it alone moves from the Waiting state to the Ready state? (Choose one.) | you cannot specify which thread will get notified.
Which declaration satisfies this requirement? (Choose one.) | public void logit(string... msgs)
A signed data type has an equal number of non-zero positive and negative values available. | false
A thread wants to make a second thread ineligible for execution. To do this, the first thread can call the yield() method on the second thread. | false
Assuming the thread is not interrupted, which one of the following statements is correct? | at line 2, the thread will stop running. it will resume running some time after 100 milliseconds have elapsed.
Which is true about the two classes? (Choose one.) | compilation of class b will fail. compilation of class a will succeed.
What value is printed out at line 6? | 101
Which of the following statements is true? (Choose one.) | the code will compile and run.
After execution, which statements are true? (Choose two.) | x[24] is 0vsx.length is 25
'What is the result? (Choose one.) | compilation fails.
calls modifies the string? (Choose one.) | none of the above
Given arrays a1 and a2, which call returns true if a1 and a2 have the same length, and a1[i].equals(a2[i]) for every legal index i? (Choose one.) | java.util.arrays.equals(a1, a2);
9. } | line 3: private; line 8: protected
A programmer wants to create an interface called B that has A as its parent. Which interface declaration is correct? (Choose one.) | public interface b extends a { }
Which code, inserted at line 14, allows the Sprite class to compile? (Choose one.) | nav.direction d = nav.direction.north;
Which code, inserted at line 15, allows the class Sprite to compile? (Choose one.) | new foo() { public int bar(){return 1; } }
Which exception or error should be thrown by the virtual machine? (Choose one.) | stackoverflowerror
and a class Circle that extends and fully implements the Shape class. Which is correct? (Choose one.) | shape s = new circle(); s.setanchor(10,10); s.draw();
What is the result? (Choose one.) | 1 2 3
What is the result? (Choose one.) | compilation fails.
What is the result? (Choose one.) | passed an assertionerror is thrown with the word "stuff" added to the stack trace.
What is the result? (Choose one.) | collie harrier
What is the result? (Choose one.) | dostuff x = 5 main x = 5
Which is true? (Choose one.) | the ownername variable breaks encapsulation.
What is the result? (Choose one.) | compilation fails due to an error in line 29.
Which is true? (Choose one.) | line 57 will print the value 3.
Which code, inserted at line 15, creates an instance of the Point class defined in Line? (Choose one.) | line.point p = new line.point();
What is the result? (Choose one.) | a exception
How can you ensure that multithreaded code does not deadlock? (Choose one.) | there is no single technique that can guarantee non-deadlocking code
How do you use the File class to list the contents of a directory? (Choose one.) | string[] contents = myfile.list();
9. catch (IOException e) { } | 8
which class should you use? (Choose one.) | treeset
In order for objects in a List to be sorted, those objects must implement which interface and method? (Choose one.) | comparable interface and its compareto method.
2. sbuf.append("-University"); | true
2. sbuf.insert(3, "-University"); | true
Is it possible to define a class called Thing so that the following method can return true under certain circumstances? boolean weird(Thing s) { Integer x = new Integer(5); return s.equals(x);} | yes
Is it possible to write code that can execute only if the current thread owns multiple locks? | yes
What is the output? | no output because of compile error at line: b = b * b1;
What is the output? | have a nice day!
What is the output? | ob1 equals ob2
What is the output? | line 4 line 6
What is the output? | line 6
Select correct statement(s) about remote class.(choose one) | all the others choices
Select correct statements about remote interface. (choose 1) | all the others choices
Select INCORRECT statement about deserialize. (choose 1) | we use readobject() method of objectoutputstream class to deserialize.
Suppose a source file contains a large number of import statements and one class definition. How do the imports affect the time required to load the class? (Choose one.) | class loading takes no additional time.
Suppose class A has a method called doSomething(), with default access. Suppose class B extends A and overrides doSomething(). Which access modes may not apply to B's version of doSomething()? (Choose one) | private
Suppose prim is an int and wrapped is an Integer. Which of the following are legal Java statements? (Choose one.) | all the above
Suppose the declared type of x is a class, and the declared type of y is an interface. When is the assignment x = y; legal? (Choose one.) | when the type of x is object
Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment xarr = yarr; legal? (Choose one.) | sometimes
Suppose you are writing a class that will provide custom deserialization.The class implements java.io.Serializable (not java.io.Extenalizable). What access mode should the readObject() method have? (Choose one.) | private
Suppose you are writing a class that will provide custom serialization. The class implements java.io.Serializable (not java.io.Externalizable). What access mode should the writeObject() method have? (Choose one.) | private
Suppose you want to create a custom thread class by extending java.lang.Thread in order to provide some special functionality. Which of the following must you do? (Choose one.) | override run().
The class is the primary class that has the driver information. | drivermanager
The element method alters the contents of a Queue. | false
There are two classes in Java to enable communication using datagrams namely. | datapacket and datasocket
URL referring to databases use the form: | protocol:subprotocol:datasoursename
if (i != null & i.intValue() == 5) System.out.println("Value is 5"); | throws an exception.
9. System.out.println("i = " + i); | the output is i = 20.
} | -1
} | the code compiles, and prints out >>null<<
10. } | an exception is thrown at line 7.
What is -8 % 5? | -3
What is the range of values that can be assigned to a variable of type byte?(Choose one.) | -2^7 through 2^7 - 1
What is the range of values that can be assigned to a variable of type short?(Choose one.) | -2^15 through 2^15 - 1
When a byte is added to a char, what is the type of the result? | int
When a negative byte is cast to a long, what are the possible values of the result? (Choose one.) | negative
When a negative long is cast to a byte, what are the possible values of the result? (Choose one.) | all the above
When a short is added to a float, what is the type of the result? | float
When comparing java.io.BufferedWriter to java.io.FileWriter, which capability exists as a method in only one of the two? (Choose one.) | writing a line separator to the stream
When you compile a program written in the Java programming language,the compiler converts the human-readable source file into platform- independent code that a Java Virtual Machine can understand. What is this platform-independent code called? | bytecode
Whenever a method does not want to handle exceptions using the try block, the is used. | throws
Which of the following are legal loop definitions? (Choose one.) | none of the above.
Which of the following are legal? (Choose two.) | double d = 1.2d;vsdouble d = 1.2d;
Which of the following are legal? (Choose two.) | int c = 0xabcd;vsint d = 0xabcd;
Which of the following are methods of the java.util.SortedSet interface?(Choose one.) | all the above
Which of the following are true? (Choose two.) | an enum may contain public method definitions.vsan enum may contain private data.
Which of the following are valid arguments to the DataInputStream constructor? (Choose one.) | fileinputstream
Which of the following are valid mode strings for the RandomAccessFile constructor? (Choose one.) | all the above
Which of the following calls may be made from a non-static synchronized method? (Choose one.) | all the above
Which of the following classes implement java.util.List? (Choose two.) | java.util.arraylistvsjava.util.stack
Which of the following classes implements a FIFO Queue? (Choose one.) | linkedlist
Which of the following interfaces does not allow duplicate objects? | set
Which of the following is not appropriate situations for assertions?(Choose one) | preconditions of a public method
Which of the following is NOTa valid comment: | /* comment
Which of the following is the most appropriate way to handle invalid arguments in a public method? | throw java.lang.illegalargumentexception.
Which of the following may legally appear as the new type (between the parentheses) in a cast operation? (Choose one.) | all of the above
Which of the following should always be caught? (Choose one.) | checked exceptions
2)A final class may not have any abstract methods. | only statement 2
} | it always returns 0.
13. } | the code compiles and execution produces the output x = 3.
16. } | the program compiles and the output is x = 104.
1. public class A { 2.    public String doit(int x, int y) { 3.       return “a”; 4.    } 5. 6.    public String doit(int... vals) { 7.       return “b”; 8.    } 9. } Given: 25. A a=new A(); 26. System.out.println(a.doit(4, 5)); What is the result? (Choose one.) | line 26 prints “a” to system.out.
1. public class A { 2.    public void method1() { 3.       B b=new B(); 4.       b.method2(); 5.      // more code here 6.    }7.} 1. public class B { 2.    public void method2() { 3.       C c=new C(); 4.       c.method3(); 5.       // more code here 6.    } 7.} 1. public class C { 2.    public void method3() { 3.        // more code here 4.    } 5.} 25. try { 26.    A a=new A(); 27.    a.method1(); 28. }catch (Exception e) { 29.    System.out.print(”an error occurred”); 30. } Which two are true if a NullPointerException is thrown on line 3 of class C? (Choose two.) | the code on line 29 will be executed.the exception will be propagated back to line 27.
______ is a set of java API  for executing SQL statements. | jdbc
______ method is used to wait for a client to initiate communications. | accept()
___________ drivers that are written partly in the Java programming language and partly in native code. These drivers use a native client library specific to the data source to which they connect. Again, because of the native code, their portability is limited. | type 2
____________ drivers that are pure Java and implement the network protocol for a specific data source. The client connects directly to the data source. | type 4
____________ drivers that use a pure Java client and communicate with a middleware server using a database-independent protocol. The middleware server then communicates the client's requests to the data source. | type 3
______________ drivers that implement the JDBC API as a mapping to another data access API, such as ODBC. Drivers of this type are generally | type 1
1. try { 2.       // assume s is previously defined 3.       URL u = new URL(s); 4.       // in is an ObjectInputStream 5.       Object o = in.readObject(); 6.       System.out.println("Success"); 7. } 8. catch (MalformedURLException e) { 9.       System.out.println("Bad URL"); 10. } 11. catch (StreamCorruptedException e) { 12.       System.out.println("Bad file contents"); 13. } 14. catch (Exception e) { 15.       System.out.println("General exception"); 16. } 17. finally { 18.       System.out.println("Doing finally part"); 19. } 20. System.out.println("Carrying on"); Where:      IOException extends Exception      StreamCorruptedException extends IOException      MalformedURLException extends IOException What lines are output if the constructor at line 3 throws a MalformedURLException? (Choose three.) | bad url doing finally part carrying on
1. try { 2.      // assume s is previously defined 3.      URL u = new URL(s); 4.      // in is an ObjectInputStream 5.      Object o = in.readObject(); 6.      System.out.println("Success"); 7. } 8. catch (MalformedURLException e) { 9.      System.out.println("Bad URL"); 10. } 11. catch (StreamCorruptedException e) { 12.      System.out.println("Bad file contents"); 13. } 14. catch (Exception e) { 15.      System.out.println("General exception"); 16. } 17. finally { 18.      System.out.println("Doing finally part"); 19. } 20. System.out.println("Carrying on"); What lines are output if the methods at lines 3 and 5 complete successfully without throwing any exceptions? (Choose three.) | success doing finally part carrying on
10. interface Foo { 11.    int bar(); 12. } 13. 14. public class Beta { 15. 16.       class A implements Foo { 17.          public int bar() { return 1; } 18.       } 19. 20.       public int fubar( Foo foo) { return foo.bar(); } 21. 22.       public void testFoo() { 23. 24.             class A implements Foo { 25.                public int bar() { return 2; } 26.             } 27. 28.             System.out.println( fubar( new A())); 29.          } 30. 31.       public static void main( String[] argv) { 32.          new Beta().testFoo(); 33.    } 34. } Which three statements are true? (Choose three.) | the code compiles and the output is 2. if lines 16, 17 and 18 were removed, the code would compile and the output would be 2. if lines 24, 25 and 26 were removed, the code would compile and the output would be 1.
10. public class ClassA { 11.    public void methodA() { 12.       ClassB classB = new ClassB(); 13.       classB.getValue();14.    } 15.} And:20. class ClassB { 21.    public ClassC classC; 22. 23.    public String getValue() { 24.       return classC.getValue(); 25.    }26.} And: 30. class ClassC { 31.    public String value; 32. 33.    public String getValue() { 34.       value = “ClassB”; 35.       return value; 36.    }37.}  ClassA a = new ClassA(); a.methodA(); What is the result?  (Choose one.) | an exception is thrown at runtime.
11. public class Bootchy { 12.    int bootch; 13.    String snootch; 14. 15.    public Bootchy() { 16.       this(”snootchy”); 17.       System.out.print(”first “); 18.    } 19. 20.    public Bootchy(String snootch) { 21.       this(420, “snootchy”); 22.       System.out.print(”second “); 23.    } 24. 25.    public Bootchy(int bootch, String snootch) { 26.       this.bootch = bootch; 27.       this.snootch = snootch; 28.       System.out.print(”third “); 29.    } 30. 31.    public static void main(String[] args) { 32.       Bootchy b = new Bootchy();33.       System.out.print(b.snootch +“ “ + b.bootch); 34.    } 35. } | third second first snootchy 420
A _____ dialog prevents user input to other windows in the application unitl the dialog is closed. | modal
A file is created with the following code: 1. FileOutputStream fos = new FileOutputStream("datafile"); 2. DataOutputStream dos = new DataOutputStream(fos); 3. for (int i=0; i<500; i++) 4.      dos.writeInt(i); You would like to write code to read back the data from this file. Which solutions will work? (Choose two.) | construct a fileinputstream, passing the name of the file. onto the fileinputstream, chain a datainputstream, and call its readint() method. construct a randomaccessfile, passing the name of the file. call the random access file’s readint() method.
A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these ways: logIt(”log message 1 “); logIt(”log message2”,”log message3”); logIt(”log message4”, “log message5”, “log message6“); Which declaration satisfies this requirement? (Choose one.) | public void logit(string... msgs)
A thread’s run() method includes the following lines: 1. try { 2.      sleep(100); 3. } catch (InterruptedException e) { } Assuming the thread is not interrupted, which one of the following statements is correct? | at line 2, the thread will stop running. it will resume running some time after 100 milliseconds have elapsed.
A(n) ___ object is used to submit a query to a database | statement
A(n) ___ object is uses to obtain a Connection to a Database | drivermanager
After execution of the following code fragment, what are the values of the variables x, a, and b? 1. int x, a = 6, b = 7; 2. x = a++ + b++; | x = 13, a = 7, b = 8
Assume that country is set for each class. Given: 10. public class Money { 11.    private String country, name; 12.    public String getCountry() { return country; } 13.} and: 24. class Yen extends Money { 25.   public String getCountry() { return super.country; } 26. } 28. class Euro extends Money { 29.   public String getCountry(String timeZone) { 30.      return super.getCountry(); 31.   } 32. } Which two are correct? (Choose two.) | euro returns correct country value. compilation fails because of an error at line 25.
Choose the valid identifiers from those listed here. (Choose all that apply.) | all: $int bytes $1 finalist bigollongstringwithmeaninglessname
Class SomeException: 1. public class SomeException { 2. } Class A: 1. public class A { 2.    public void doSomething() { } 3. } Class B: 1. public class B extends A { 2.    public void doSomething() throws SomeException { } 3. } Which is true about the two classes?  (Choose one.) | compilation of class b will fail. compilation of class a will succeed.
Class TestException:1. public class TestException extends Exception { 2. } Class A: 1. public class A { 2. 3.    public String sayHello(String name)   throws TestException { 4. 5.       if(name == null) { 6.          throw new TestException(); 7.       } 8. 9.       return “Hello “+ name; 10.   } 11. 12. } A programmer wants to use this code in an application: 45. A a=new A(); 46. System.out.println(a.sayHello(”John”)); Which two are true? (Choose two.) | line 46 will compile if the enclosing method throws a testexception. line 46 will compile if enclosed in a try block, where testexception is caught.
1. class Q6 {2.      public static void main(String args[]) {3.           Holder h = new Holder();4.           h.held = 100;5.           h.bump(h);6.           System.out.println(h.held);7.      }8. }9.10. class Holder {11.      public int held;12.      public void bump(Holder theHolder) {13.           theHolder.held++; 14        }15.  }15. }What value is printed out at line 6? | 101
1. class Q7 { 2.       public static void main(String args[]) { 3.             double d = 12.3; 4.             Decrementer dec = new Decrementer(); 5.             dec.decrement(d); 6.             System.out.println(d); 7.       } 8. } 9. 10. class Decrementer {11.       public void decrement(double decMe) { 12.             decMe = decMe - 1.0; 13.       } 14. } What value is printed out at line 6? | 12.3
1. public class Test extends Base { 2.       public Test(int j) { 3.       }  4.       public Test(int j, int k) { 5.             super(j, k); 6.       } 7. } Which of the following are legitimate calls to construct instances of the Test class? (Choose two.) | test t = new test(1); test t = new test(1, 2);
1. public class Test extends Base { 2.      public Test(int j) { 3.      } 4.      public Test(int j, int k) { 5.           super(j, k); 6.      } 7. } Which of the following forms of constructor must exist explicitly in the definition of the Base class? Assume Test and Base are in the same package. (Choose two.) | base() { } base(int j, int k) { }
1. class Cruncher { 2.      void crunch(int i) { 3.           System.out.println("int version"); 4.      } 5.      void crunch(String s) { 6.           System.out.println("String version"); 7.     } 8. 9.      public static void main(String args[]) { 10.           Cruncher crun = new Cruncher(); 11.           char ch = "p"; 12.           crun.crunch(ch); 13.      } 14. } Which of the following statements is true? (Choose one.) | the code will compile and produce the following output: int version.
1. public class Base { 2.       public void method(int i) { 3.             System.out.print(“Value is “ + i); 4.       } 5. } 1. public class Sub extends Base { 2.       public void method(int j) { 3.             System.out.print(“This value is “ + j); 4.       } 5.       public void method(String s) { 6.             System.out.print(“I was passed “ + s); 7.       } 8.       public static void main(String args[]) { 9.             Base b1 = new Base(); 10.           Base b2 = new Sub(); 11.           b1.method(5); 12.           b2.method(6); 13.     } 14. }  What output results when the main method of the class Sub is run?(Choose one.) | value is 5this value is 6
Which line will not compile? (Choose one.) 1. Object ob = new Object(); 2. String[] stringarr = new String[50]; 3. Float floater = new Float(3.14f); 4. ob = stringarr; 5. ob = stringarr[5]; 6. floater = ob; 7. ob = floater; | line 6
1. public class Assertification { 2.      public static void main(String[] args) { 3.           assert args.length == 0; 4      } 5. } Which of the following conditions must be true in order for the code to throw an AssertionError? Assume you are using release 5.0. (Choose two.) | the args array must have one or more elements. the application must be run with the -enableassertions flag or another assertionenabling flag.
1. StringBuffer sbuf = new StringBuffer(); 2. sbuf = null; 3. System.gc();  Choose true statement. (Choose one.) | after line 2 executes, the stringbuffer object is eligible for garbage collection.
1. Cat sunflower; 2. Washer wawa; 3. SwampThing pogo; 4. 5. sunflower = new Cat(); 6. wawa = sunflower; 7. pogo = (SwampThing)wawa;  Which of the following statements is true? (Choose one.) Where:     Mammal extends Animal    Cat,  SwampThing extends Mammal    Cat implements Washer | the code will compile but will throw an exception at line 7, because the runtime class of wawa cannot be converted to type swampthing.
1. Dog rover, fido; 2. Animal anim; 3. 4. rover = new Dog(); 5. anim = rover; 6. fido = (Dog)anim;  Where:       Mammal extends Animal       Dog extends Mammal  Which of the following statements is true? (Choose one.) | the code will compile and run, but the cast in line 6 is not required and can be eliminated.
1. for (int i = 0; i < 2; i++) { 2.      for (int j = 0; j < 3; j++) { 3.           if (i == j) { 4.                continue; 5.           } 6.           System.out.println("i = " + i + " j = " + j); 7.      } 8. } Which lines would be part of the output? (Choose four.) | 0-1 0-2 1-0 1-2
1. outer: for (int i = 0; i < 2; i++) { 2.      for (int j = 0; j < 3; j++) { 3.           if (i == j) { 4.                continue outer; 5.           } 6.           System.out.println("i = " + i + " j = " + j); 7.      } 8. }  Which lines would be part of the output? (Choose one.) | i = 1 j = 0
1. Raccoon rocky; 2. SwampThing pogo; 3. Washer w; 4. 5. rocky = new Raccoon(); 6. w = rocky; 7. pogo = w;  Which of the following statements is true? (Choose one.) Where:     Mammal extends Animal     Dog, Raccoon, Swamp Thing extends Mammal     Raccoon implements Washer | line 7 will not compile; an explicit cast is required to convert a washer to a swampthing
1. public class Outer { 2.      public int a = 1; 3.      private int b = 2; 4.      public void method(final int c) { 5.           int d = 3, f=10; 6.           class Inner { 7.                private void iMethod(int e) { 8. 9.                } 10.           } 11.      } 12. }  Which variables can be referenced at line 8? (Choose four.) | abce
int[] x = new int[25];  After execution, which statements are true? (Choose two.) | x[24] is 0 x.length is 25
1. public class Test1 { 2.      public float aMethod(float a, float b)  throws IOException {.. } 3. }  1. public class Test2 extends Test1 { 2. 3.}  Which of the following methods would be legal (individually) at line 2 in class Test2? (Choose two) | public int amethod(int a, int b) throws exception {...} public float amethod(float p, float q) {...}
1. public class Test1 { 2.      public float aMethod(float a, float b) { 3.      } 4. 5. } Which of the following methods would be legal if added (individually) at line 4? (Choose three.) | public int amethod(int a, int b) { } public float amethod(float a, float b, int c) throws exception { } private float amethod(int a, int b, int c) { }
11. public static Iterator reverse(List list) { 12.    Collections.reverse(list); 13.    return list.iterator(); 14. } 15. public static void main(String[] args) { 16.    List list = new ArrayList(); 17.    list.add(” 1”); list.add(”2”); list.add(”3”); 18.      for (Object obj: reverse(list)) 19.        System.out.print(obj + “,”); 20. } ‘What is the result?  (Choose one.) | compilation fails.
Given a string constructed by calling s = new String("xyzzy"), which of the calls modifies the string? (Choose one.) | none of the above
Given the following class: public class Xyz implements java.io.Serializable {       public int iAmPublic;       private int iAmPrivate;       static int iAmStatic;       transient int iAmTransient;       volatile int iAmVolatile;        } Assuming the class does not perform custom serialization, which fields are written when an instance of Xyz is serialized? (Choose three.) | iampublic iamprivate iamvolatile
Given the following code, and making no other changes, which combination of access modifiers (public, protected, or private) can legally be placed before aMethod() on line 3 and be placed before aMethod() on line 8? (Choose one.) 1. class SuperDuper 2. { 3.      void aMethod() { } 4. } 5. 6. class Sub extends SuperDuper 7. { 8.      void aMethod() { } 9. } | line 3: private; line 8: protected
enum Spice { NUTMEG, CINNAMON, CORIANDER, ROSEMARY; } | spice sp = spice.nutmeg; object ob = sp; spice sp = spice.nutmeg; object ob = (object)sp;object ob = new object(); spice sp = (spice)ob;
List<String> names = new ArrayList<String>(); which of the following are legal? (Choose two.) | iterator<string> iter = names.iterator(); for (string s:names)
11. static class A { 12.    void process() throws Exception {  throw new Exception(); } 13. } 14. static class B extends A { 15.    void process() { System.out.println(”B “);  }16.  } 17.public static void main(String[] args) { 18.       A a=new B(); 19.       a.process(); 20.  }What is the result?  (Choose one.) | compilation fails line 19.
public class Bar {       public static void main(String [] args) { 		int x =5; 		boolean b1 = true; 		boolean b2 = false;		if((x==4) && !b2) 		    System.out.print("l ");      	                     System.out.print("2 "); 		if ((b2 = true) && b1)		    System.out.print("3"); 	        }}What is the result? (Choose one.) | 2 3
1. public interface A { 2.     String DEFAULT_GREETING = “Hello World”; 3.     public void method1(); 4. } A programmer wants to create an interface called B that has A as its parent. Which interface declaration is correct? (Choose one.) | public interface b extends a { }
10. abstract public class Employee { 11.    protected abstract double getSalesAmount(); 12.    public double getCommision() { 13.       return getSalesAmount() * 0.15; 14.    } 15. } 16. class Sales extends Employee { 17. // insert method here 18. } Which two methods, inserted independently at line 17, correctly complete the Sales class? (Choose two.) | public double getsalesamount() { return 1230.45; } protected double getsalesamount() { return 1230.45; }
10. class MakeFile { 11.    public static void main(String[] args) { 12.       try { 13.          File directory = new File(”d”); 14.          File file = new File(directory,”f”); 15.          if(!file.exists()) { 16.             file.createNewFile(); 17.          } 18.       }catch (IOException e) { 19.          e.printStackTrace ();20.       } 21.    } 22. } The current directory does NOT contain a directory named “d.” Which three are true? (Choose three.) | an exception is thrown at runtime. line 13 creates a file object named “d.” line 14 creates a file object named “f.’
10. class Nav{ 11.       public enum Direction { NORTH, SOUTH, EAST, WEST } 12. } 13. public class Sprite{ 14. // insert code here 15. } Which code, inserted at line 14, allows the Sprite class to compile? (Choose one.) | nav.direction d = nav.direction.north;
10. interface Foo { int bar(); } 11. public class Sprite { 12.    public int fubar( Foo foo) { return foo.bar(); } 13.    public void testFoo() { 14.       fubar( 15.       // insert code here 16.       ); 17. } 18. } Which code, inserted at line 15, allows the class Sprite to compile? (Choose one.) | new foo() { public int bar(){return 1; } }
10. public class ClassA { 11.    public void count(int i) { 12.       count(++i); 13.    } 14. } And: 20. ClassA a = new ClassA(); 21. a.count(3); Which exception or error should be thrown by the virtual machine?  (Choose one.) | stackoverflowerror
11. public abstract class Shape { 12.    int x; 13.    int y; 14.    public abstract void draw(); 15.    public void setAnchor(int x, int y) { 16.       this.x = x; 17.       this.y = y; 18.    } 19. } and a class Circle that extends and fully implements the Shape class. Which is correct? (Choose one.) | shape s = new circle(); s.setanchor(10,10); s.draw();
11. public static void main(String[] args) { 12.    Object obj =new int[] { 1,2,3 }; 13.    int[] someArray = (int[])obj; 14.    for (int i: someArray) System.out.print(i +" ");15. } What is the result? (Choose one.) | 1 2 3
11. public static void main(String[] args) { 12.    try { 13.       args=null; 14.       args[0] = “test”; 15.       System.out.println(args[0]); 16.    }catch (Exception ex) { 17.       System.out.println(”Exception”); 18.    }catch (NullPointerException npe) { 19.       System.out.println(”NullPointerException”); 20.    } 21. } What is the result?  (Choose one.) | compilation fails.
11. public static void parse(String str) { 12.    try { 13.       float f= Float.parseFloat(str); 14.    } catch (NumberFormatException nfe) { 15.       f = 0; 16.    } finally { 17.       System.out.println(f); 18.    } 19. } 20. public static void main(String[] args) { 21.    parse("invalid"); 22. } What is the result? (Choose one.) | compilation fails.
11. String test = “This is a test”; 12. String[] tokens = test.split(”\s”); 13. System.out.println(tokens.length); What is the result?  (Choose one.) | compilation fails.
12. public class AssertStuff { 14.    public static void main(String [] args) { 15.       int x= 5; 16.       int y= 7; 18.       assert (x > y): “stuff”; 19.       System.out.println(”passed”); 20.    } 21. } And these command line invocations: java AssertStuff java -ea AssertStuff What is the result?  (Choose one.) | passed an assertionerror is thrown with the word “stuff” added to the stack trace.
12. public class Test { 13.    public enum Dogs {collie, harrier}; 14.    public static void main(String [] args) { 15.       Dogs myDog = Dogs.collie; 16.       switch (myDog) { 17.          case collie: 18.             System.out.print(”collie “); 19.          case harrier: 20.             System.out.print(”harrier “); 21.       } 22.    } 23. } What is the result?  (Choose one.) | collie harrier
13. public class Pass { 14.     public static void main(String [] args) { 15.       int x = 5; 16.       Pass p = new Pass(); 17.       p.doStuff(x); 18.       System.out.print(" main x = "+ x); 19.     } 20. 21.     void doStuff(int x) { 22.       System.out.print("doStuff x = "+ x++); 23.     } 24. } What is the result? (Choose one.) | dostuff x = 5 main x = 5
13. public class Pass { 14.     public static void main(String [] args) { 15.       int x = 5; 16.       Pass p = new Pass(); 17.       p.doStuff(x); 18.       System.out.print(" main x = "+ x); 19.     } 20. 21.     void doStuff(int x) { 22.       System.out.print("doStuffx = "+ x++); 23.     } 24. } What is the result? (Choose one.) | dostuffx = 5 main x = 5
public class Q { public static void main(String argv[]){ int anar[]=new int[]{1,2,3}; System.out.println(anar[1]); | 2
Which of the following statements is INCORRECT | a method in an interface can access class level variables
Which of the following is legal? | double d = 1.2d;
Which of the following operations might throw an ArithmeticException? | %
class Base {} class Sub extends Base {} class Sub2 extends Base {} public class CEx {     public static void main(String argv[]) {        Base b = new Base();        Sub s = (Sub) b;     }} | compile time exception
Which of the following statements is incorrect | vector does not allow duplicate elements
select the most correct statement | a (non-local) inner class may be declared as public, protected, private, static, final or abstract.
which of the following statements is true about two base protocols used for networking: TCP (Transmissions Control Protocol) and UDP (User Datagram Protocol)? | tcp is a connection-based protocol and udp is not connection-based protocol
Which of the statements below are true? | to check whether the file denoted by the abstract pathname is a directory or not, call the isdirectory() method of the file class
public class Main{     public static void main(String argv[]){         String s = "Hi there";         int pos = s.indexOf(" ");         String r = s.substring(0,pos);         String s2 = new String(new char[]{'H','i'});         if (r.equals(s2))             System.out.println("EQUAL");         else              System.out.println("NOT EQUAL");         System.out.println("");     } } | equal
which of the following methods of the collections class can be used to find the largest value in a vector? | collection.max()
select the correct statement which set the layout manager of a given frame to flowlayoutmanager | setlayout(new flowlayout());
public class Bground extends Thread{ public static void main(String argv[]){                 Bground b = new Bground();                 b.run();         }         public void start(){                 for (int i = 0; i <10; i++){                         System.out.println("Value of i = " + i);                 }         } } | clean compile but no output at runtime
public class EqTest{ public static void main(String argv[]}{ EqTest e = new EqTest(); } | if(s.equalsignorecase(s2))
public class Main {      public static void main(String Argv[]) {         A t = new A("One");         t.run();         A h = new A("Two");         h.run();     } }  class A extends Thread {      private String sTname = "";      A(String s) {         sTname = s;     } } public void run(){     for(int i =0;i<2;i++){         try{         sleep(1000);  }   catch(InterruptedException e){}      yield();     System.out.print(sTname+"");     } } | compile time error, class rpcraven does not import java.lang.thread
abstract class Base{        abstract public void myfunc();        public void another(){        System.out.println("Another method");        }}public class Abs extends Base{        public static void main(String argv[]){        Abs a = new Abs();        a.amethod();        }        public void myfunc(){                System.out.println("My Func");                }         public void amethod(){        myfunc();              }} | the code will compile and run, printing out the words "my func"
public class MyMain{ public static void main(String argv){         System.out.println("Hello cruel world");         } } | the code will compile but will complain at run time that main is not correctly defined
Which of the following are Java modifiers? | public private transient
class Base{        abstract public void myfunc();        public void another(){        System.out.println("Another method");        }}public class Abs extends Base{        public static void main(String argv[]){        Abs a = new Abs();        a.amethod();        }        public void myfunc(){                System.out.println("My func");                }         public void amethod(){        myfunc();        }} | the compiler will complain that the base class is not declared as abstract.
which of the following methods of java.io.file can be used to create a new file | there is no such method. just do file f = new file("filename.txt"), then the new file, named filename.txt will be created
Why might you define a method as native? | to get to access hardware that java does not know about to write optimised code for performance in a language such as c/c++
class Base{ public final void amethod(){         System.out.println("amethod");         } }  public class Fin extends Base{ public static void main(String argv[]){         Base b = new Base();         b.amethod();         } } | success in compilation and output of "amethod" at run time.
public class Mod{ public static void main(String argv[]){     }         public static native void amethod();  } | compilation and execution without error
private class Base{} public class Vis{         transient int  iVal;         public static void main(String elephant[]){         } } | compile time error: base cannot be private
//File P1.java package MyPackage; class P1{ void afancymethod(){         System.out.println("What a fancy method");         } } //File P2.java public class P2 extends P1{     public static void main(String argv[]){ 	P2 p2 = new P2(); 	p2.afancymethod();     }} | p1 compiles cleanly but p2 has an error at compile time
public class MyAr{ public static void main(String argv[]){         int[] i = new int[5];         System.out.println(i[5]);         } } | an error at run time
20. public class CreditCard { 22. private String cardlD; 23. private Integer limit; 24. public String ownerName; 26. public void setCardlnformation(String cardlD, 27. String ownerName, 28. Integer limit) { 29. this.cardlD = cardlD; 30. this.ownerName = ownerName; 31. this.limit = limit; 32. } 33. } | the ownername variable breaks encapsulation.
23. Object [] myObjects = { 24. new Integer(12), 25. new String(”foo”), 26. new Integer(5), 27.new Boolean(true) 28. }; 29. java.util.Array.sort(myObjects); 30. for( int i=0; i<myObjects.length; i++) { 31. System.out.print(myObjects[i].toString()); 32. System.out.print(” “); 33. } What is the result? (Choose one.) | compilation fails due to an error in line 29.
31. // some code here 32. try { 33. // some code here 34. } catch (SomeException se) { 35. // some code here 36. } finally { 37. // some code here 38. } Under which three circumstances will the code on line 37 be executed? (Choose three.) | the code on line 33 throws an exception. the code on line 35 throws an exception. the code on line 33 executes successfully.
33. try { 34. // some code here 35. }catch (NullPointerException e1) { 36.    System.out.print(”a”); 37. }catch (RuntimeException e2) { 38.    System.out.print(”b”); 39. } finally { 40.     System.out.print(”c”); 41. } What is the result if a NullPointerException occurs on line 34?  (Choose one.) | ac
55. int []x= {1, 2,3,4, 5}; 56. int y[] =x; 57. System.out.println(y[2]); Which is true? (Choose one.) | line 57 will print the value 3.
8. public class test { 9.     public static void main(String [] a) { 10.        assert a.length == 1; 11.    } 12.} Which two will produce an AssertionError? (Choose two.) | java -ea test, java -ea test file1 file2
1. public class TestString3 { 2.    public static void main(String[] args) { 3.       // insert code here 5.       System.out.println(s); 6.    } 7. } Which two code fragments, inserted independently at line 3, generate the output 4247? (Choose two.) | stringbuffer s = new stringbuffer(”123456789”); s.delete(0,3).replace( 1,3, “24”).delete(4,6); stringbuilder s = new stringbuilder(”123456789”); s.delete(0,3).delete( 1 ,3).delete(2,5).insert( 1, “24”);
10. class Line { 11.    public static class Point { } 12. } 13. 14. class Triangle { 15. // insert code here 16. } Which code, inserted at line 15, creates an instance of the Point class defined in Line?  (Choose one.) | line.point p = new line.point();
10. public class Bar { 11.	static void foo(int...x) { 12.	// insert code here 13. } 14. } Which two code fragments, inserted independently at line 12, will allow the class to compile? (Choose two.) | for(int z : x) system.out.println(z); for( int i=0; i< x.length; i++ )   system.out.println(x[i]);
11. public interface Status { 12. /* insert code here */ int MY_VALUE = 10; 13. } Which three are valid on line 12? (Choose three.) | final static public
class A {   public void process() { System.out.print("A "); }   public static void main(String[] args) { try { ((A)new B()).process(); } catch (Exception e) {  System.out.print("Exception ");   }   }}class B extends A {   public void process() throws RuntimeException {      super.process();      if (true) throw new RuntimeException();      System.out.print("B");   }} | a exception b
How can you ensure that multithreaded code does not deadlock? (Choose one.) | there is no single technique that can guarantee non-deadlocking code.
How can you force garbage collection of an object? (Choose one.) | garbage collection cannot be forced.
How do you prevent shared data from being corrupted in a multithreaded environment? (Choose one.) | access the variables only via synchronized methods.
How many bytes does the following code write to file dest? (Choose one.) 1. try { 2. FileOutputStream fos = newFileOutputStream("dest"); 3. DataOutputStream dos = new DataOutputStream(fos); 4. dos.writeInt(3); 5. dos.writeFloat(0.0001f); 6. dos.close(); 7. fos.close(); 8. } 9. catch (IOException e) { } | 12
How many locks does an object have? (Choose one.) | one
If all three top-level elements occur in a source file, they must appear in which order? (Choose one.) | package declaration, imports, class/interface/enum definitions.
If class Y extends class X, the two classes are in different packages, and class X has a protected method called abby(), then any instance of Y may call the abby() method of any other instance of Y. | false
If you attempt to compile and execute the following application, will it ever print out the message In xxx? 1. class TestThread3 extends Thread { 2.       public void run() { 3.             System.out.println("Running"); 4.             System.out.println("Done"); 5.       } 6. 7.       private void xxx() { 8.             System.out.println(“In xxx”); 9.       } 10. 11.      public static void main(String args[]) { 12.             TestThread3 ttt = new TestThread3();  13.             ttt.xxx(); 14.             ttt.start(); 12.       } 13. } | yes
If you need a Set implementation that provides value-ordered iteration, which class should you use?  (Choose one.) | treeset
In order for objects in a List to be sorted, those objects must implement which interface and method?  (Choose one.) | comparable interface and its compareto method.
In the following code fragment, after execution of line 1, sbuf references an instance of the StringBuffer class. After execution of line 2, sbuf still references the same instance. 1. StringBuffer sbuf = new StringBuffer("FPT"); 2. sbuf.append("-University"); | true
In the following code fragment, after execution of line 1, sbuf references an instance of the StringBuffer class. After execution of line 2, sbuf still references the same instance. 1. StringBuffer sbuf = new StringBuffer("FPT"); 2. sbuf.insert(3, "-University"); | true
In the following code, what are the possible types for variable result? (Choose the most complete true answer.) 1. byte b = 11; 2. short s = 13; 3. result = b * ++s; | int, long, float, double
Interface ____ helps manage the connection between a Java program and a database | connection
Is it possible to define a class called Thing so that the following method can return true under certain circumstances? boolean weird(Thing s) {     Integer x = new Integer(5);     return s.equals(x); } | yes
JDBC supports ______ and ______ models. | two-tier and three-tier
public class Test{ public static void main(String[] args){ byte b = 2; byte b1 = 3; b = b * b1; System.out.println("b="+b);	} } What is the output? | no output because of compile error at line:  b = b * b1;
public class Test{ public static void main(String[] args){ Object ob1= new Object(); Object ob2= new Object(); if(ob1.equals(ob2)) System.out.println("ob1 equals ob2"); if(ob1==ob2)  System.out.println("ob1==ob2");	System.out.println("Have a nice day!");	} } What is the output? | have a nice day!
public class Test{ public static void main(String[] args){ Object ob1= new Object(); Object ob2= ob1; if(ob1.equals(ob2)) System.out.println("ob1 equals ob2"); if(ob1==ob2)  System.out.println("ob1==ob2"); System.out.println("Have a nice day!");	} } What is the output? | ob1 equals ob2 ob1==ob2 have a nice day!
public class Test{ public static void main(String[] args){ String s1 = "xyz"; String s2 = "xyz"; if (s1 == s2) System.out.println("Line 4"); if (s1.equals(s2)) System.out.println("Line 6");	} } What is the output? | line 4 line 6
public class Test{ public static void main(String[] args){ String s1 = "xyz"; String s2 = new String("xyz"); if (s1 == s2) System.out.println("Line 4"); if (s1.equals(s2)) System.out.println("Line 6");} } What is the output? | line 6
public class Test{ public static void main(String[] args){ String s1 = "xyz"; String s2 = new String(s1); s2.intern(); if (s1 == s2) System.out.println("Line 4"); if (s1.equals(s2)) System.out.println("Line 6");} } What is the output? | line 6
public class Test{	public static void main(String[] args){		String s1 = "xyz";		String s2 = new String(s1);		s2=s2.intern();		if (s1 == s2)     		   System.out.println("Line 4");     	                     if (s1.equals(s2))     		   System.out.println("Line 6");	} } What is the output? (choose 1) | line 4 line 6
Select correct statement about RMI. (choose 1) | all the above
Select INCORRECT statement about  serialization. (choose 1) | when an object output stream serializes an object that contains references to another object, every referenced object is not serialized along with the original object.
Select incorrect statement about RMI server.(choose 1) | a client accesses a remote object by specifying only the server name.
Select incorrect statement about ServerSocket class. (choose 1) | to make the new object available for client connections, call its accept() method, which returns an instance of serversocket
Select incorrect statement about Socket class. (choose 1) | the java.net.socket class contains code that knows how to find and communicate with a server through udp
Select the correct statement about JDBC two-tier processing model. | a user's commands are delivered to the database or other data source, and the results of those statements are sent back to the user.
Statement objects return SQL query results as ___ objects | resultset
Study the statements: 1)When a JDBC connection is created, it is in auto-commit mode 2)Once auto-commit mode is disabled, no SQL statements will be committed until you call the method commit explicitly | both 1 and 2 are true
Suppose a method called finallyTest() consists of a try block, followed by a catch block, followed by a finally block. Assuming the JVM doesn’t crash and the code does not execute a System.exit() call, under what circumstances will the finally block not begin to execute? (Choose one.) | if the jvm doesn't crash and the code does not execute a system.exit() call, the finally block will always execute.
Suppose a source file contains a large number of import statements. How do the imports affect the time required to compile the source file? (Choose one.) | compilation takes slightly more time.
Suppose class A extends Object; Class B extends A; and class C extends B. Of these, only class C implements java.io.Externalizable. Which of the following must be true in order to avoid an exception during deserialization of an instance of C? (Choose one.) | c must have a no-args constructor.
Suppose class A extends Object; class B extends A; and class C extends B. Of these, only class C implements java.io.Serializable. Which of the following must be true in order to avoid an exception during deserialization of an instance of C? (Choose one.) | b must have a no-args constructor.
Suppose class A has a method called doSomething(), with default access. Suppose class B extends A and overrides doSomething(). Which access modes may not apply to B’s version of doSomething()? (Choose one) | private
Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides doSomething(). What access modes may Subby’s version of the method have? (Choose two.) | public protected
Suppose class X contains the following method: void doSomething(int a, float b) { … } Which of the following methods may appear in class Y, which extends X? (Choose one.) | public void dosomething(int a, float b) { … }
Suppose interface Inty defines five methods. Suppose class Classy declares that it implements Inty but does not provide implementations for any of the five interface methods. Which are true? (Choose two.) | the class will compile if it is declared abstract. the class may not be instantiated.
Suppose salaries is an array containing floats. Which of the following are valid loop control statements for processing each element of salaries? (Choose one.) | for (float f:salaries)
Suppose x and y are of type TrafficLightState, which is an enum. What is the best way to test whether x and y refer to the same constant? (Choose one.) | if (x == y)
Suppose you are writing a class that will provide custom deserialization. The class implements java.io.Serializable (not java.io.Externalizable). What access mode should the readObject() method have? (Choose one.) | private
Swing components cannot be combined with AWT components. | true
The ______ class is the primary class that has the driver information. | drivermanager
The ______ class is used to implement a pull-down menu that provides a number of items to select from. | menu
The border layout resizes the ______ components to fill the remaining centre space. | center
public class MyClass1 { public static void main(String argv[]) {} /*Modifier at XX*/ class MyInner {} } What modifier would be illegal at XX in the above code? | friend
What will happen when you attempt to compile and run this code? class Base{ abstract public void myfunc(); public void another(){ System.out.println("Another method"); }} public class Abs extends Base{ public static void main(String argv[]){ Abs a = new Abs(); a.amethod(); } public void myfunc(){ System.out.println("My func"); } public void amethod(){ myfunc(); } } | the compiler will complain that the base class is not declared as abstract
Given the following class definition, which if the following methods could be legally placed after the comment //Here? (Select two) public class Rid{ public void amethod(int i, String s){} //Here } | public void amethod(int i, string s){} public void amethod(string s, int i){}
Select correct statement (1) The Swing's list component(JList) can display text only (2) The Swing's button(JButton) can not contain an image. (3) The Swing's label(JLabel) can present an image | 1 3
What is the output of the following code: class Main{ public static void main(String[] argv){ byte b1 = 10; byte b2 = 9; b1 = (byte)(b1 | b2); system.out.println(b1); }}  |  11
What is the purpose of the finally clause of a try-catch-finally statement? (Select correct answer) | the finally clause is used to provide the capability to execute code no matter whether or matter whether or not an exception is throw or caught
Consider the following class:1. class Test {2.      void foo(int i) {3.           System.out.println("int version");4.      }5.      void foo(String s) {6.           System.out.println("String version");7.     }8.9.      public static void main(String args[]) {10.           Test t = new Test();11.           char ch = 'p';12.           t.foo(ch);13.      }14. }Which of the following statements is true? | the code will compile and produce the following output: int version.
What will happen when you try compiling and running this code? public class Ref{ public static void main(String argv[]){ Ref r = new Ref(); r.amethod(r); } public void amethod(Ref r){ int i = 99; multi(r); System.out.println(i); } public void multi(Ref r){ r.i = r.i*2; }} | error at compile time
Which of following Java operations cause compile-time errors? int m=5, n=7; float x=m; //1 double y=n; //2 m = y; //3 n = x; //4 | 3, 4
Select correct statement(s). (Select one option only) (1) Swing is part of the Java Foundation Classes and provides a rich set of GUI components. (2) Before you think about what your GUI will look like, it's important to think about what it will. | 1, 2
With respect to processing models for database access, in the ... model a Java application talks directly to the data source | two-tier
What will happen when you attempt to compile and run the following program (please note that the Object class does not have the foo() method): class A{ void foo(){ System.out.print("A");}} class B{ void foo(){ System.out.print("B");}} class C extends A{ void foo(){ System.out.print("C");}} class Main{ public static void main(String[] args){ Object t = new A(); t.foo(); t = new B(); t.foo(); t = new C(); t.foo(); } } | compile-time error
What is the output of the following code: class Main{ public static void main(String args[]){ int k=11; System.out.print(k>>3); System.out.print(4&3); System.out.print(4 | 3); system.out.println(); }}  |  107
Suppose class X contains the following method: void doSomething(int a, float b){ ... } Which of the following methods may appear in class Y, which extends X? | public void dosomething(int a, float b){ ... }
int j; for(int i=0; i<14; i++){ if(i<10){ j = 2 + i; } System.out.println("j: " + j + "i: " +i); } What is WRONG with the above code? | integer "j" is not initialized.
What is -8%5? | -3
What happens when you try to compile and run the following program? import java.ulti.*; public class Main{ public static void main(String args[]){ String s = "ABC 4 5 6 8"; Scanner sc = new Scanner(s); sc.next(); System.out.println(sc.nextInt() + sc.nextInt() + sc.nextInt()); }} | the program will have a runtime exception.
Which is the INCORRECT answer for the following question: What can cause a thread to stop executing? | a call to the halt method of the thread class
Which of the following classes supports developers to get the pointer of a file? | java.io.randomaccessfile
Which of the following is Java keyword? | new
With respect to steps in RMI implementation: (1) Create the remote interface (2) Create the remote object (3) Create the client object (4) Create the Stub The order should be followed: | 1, 2, 4, 3
Give the following code, which of the following will not compile? enum Spice{ NUTMEG, CINNAMON, CORIANDER, ROSEMARY; } | string ob = new string(); spice sp = ob;
Select the correct statement: | an object reference can be cast to an interface reference when the object implements the referenced interface.
The default layout manager for every JPane is | flowlayout
Which of the following is NOT a valid comment | /*comment
Suppose salaries is an array containing floats. Which of the following are valid loop control statements for processing each element of salaries? | for(float f:salaries)
With respect to networking and the client-server model. (1) A server runs on a specific computer and has a socket that is bound to a specific port number. The server just waits, listening to the socket for a client to make a connection request.(2) To connect to the server, the client must know the hostname or IP of the machine on which the server is running and the port number on which the server is listening | true, true.
With respect to networking and the client-server model. (1) A socket is one endpoint (a combination of an IP address and a port number) of a two-way communication link between two programs running on the network..(2) TCP (Transmission Control Protocol) is a connection-based protocol that provides a reliable flow of data between two computers.(3) UDP (User Datagram Protocol) is a protocol that sends independent packets of data, called datagrams, from one computer to another with no guarantees about arrival. | true, true, true
How do you change the value of the object k that is encapsulated by a wrapper class after you have instantiated it? | use the k.setxxx() method defined for the wrapper class
What happens when you try to compile and run the following program? import java.ulti.*; public class Main{ public static void main(String argv[]){ Vector<Integer> t = new Vector<Integer>(); t.add(12); t.add(2); t.add(5); t.add(2); Iterator<Integer> i = t.iterator(); int sum=0; while(i.hasNext()) sum += i.next(); System.out.println(sum); }} | the program will print out 21
Which of the following are true? (Select two) | system.out has a println() method. system.out has a format() method.
What will happen when you attempt to compile and run the following program: class Box{ int a,b; Box(){} Box(int x, int y){a=x;b=y;} } class Reg extends Box{ int c; Reg(){} Reg(int x, int y, int z){ this.c = z; super(x,y); } void display(){ System.out.println(a+b+c); }} class Main{ public static void main(String[] args){ Reg t = new Reg(2,3,4); t.display(); }} | compile time error
What results from running the following code? 1. public class Xor{ 2. public static void main(String args[]){ 3. byte b = 10; //00001010 binary 4. byte c = 15; //00001111 binary 5. b = (byte)(b ^ c); 6. System.out.println("b contains " + b); 7. } 8. } | the output: b contains 5
Which component can display an image, but cannot get focus? | jlabel
Which of the following is legal loop construction? | int j = 0; for(int k=0; j+k != 10; j++, k++){ system.out.println("j=" + j + ", k="+k); }
import java.util.*; public class Main{ public static void main(String argv[]){ String s = "ABCk23k5.9"; Scanner t = new Scanner(s); t.useDelimiter("[k]");//use the character k as delimiter String u = t.next(); while(t.hasNext()) u += t.next(); System.out.println(u.substring(2)); }} | c235.9
Which of the following best describes the use of the synchronized keyword? | ensures only one thread at a time may access a method or object
Select the order of access modifiers from least restrictive to most restrictive. | public, protected, default, private
When is x & y an int? | when neither x nor y is a float, or a double
What will be printed out if this code is run with the following command line? java mypro good morning public class mypro{ public static void main(String argv[]){ System.out.println(argv[2]); }} | exception raised "java.lang.arrayindexoutofboundsexception: 2"
class Test{ public int fun(int x){ int count=1; try{ count += x; foo(count); count++; } catch(Exception e){ count -= x; } return (count); }    public int foo(int k){ if(true) throw new ArithmeticException(); return(k);}} class Main{ public static void main(String[] args){ Test t = new Test(); System.out.println(t.fun(2)); }}} | 1
public int fubar(Foo foo){ return foo.bar(); } public void testFoo(){ class A implements Foo{ public int bar(){ return 2; } } System.out.println(fubar(new A())); } public static void main(String[] argv){ new Beta().testFoo(); } } Which statement is true? | the code compiles and the output is 2
class Base{ public void Base(){ System.out.println("Base"); } } public class In extends Base{ public void main(String argv[]){ In i = new In(); } } | compilation and no output at runtime
Which of the following are true? (Select two) | once the thread terminates, it cannot be restarted by calling the function start() again when a thread terminates its processing, it enters the dead state
Which of the following are true about garbage collection? | garbage collection does not guarantee that a program will not run out of memory
What will be printed out if you attempt to compile and run the following code? int i=9; switch(i){ default: System.out.println("default"); case 0: System.out.println("zero"); break; case 1: System.out.println("one"); case 2: System.out.println("two"); } | default zero
Which of the following is INCORRECT? | char c = \u1234;
Which of the following statements is true? | constructors are not inherited
public class C{ public void method3(){ //more code here }} try{ A a = new A(); a.method1(); }catch(Exception e){ System.out.print("an error occurred"); } Which is true if a NullPointerException is thrown on line 3 of class C? | the code on line 29 will be executed.
Which of the following statements is true? | given that inner is a nonstatic class declared inside a public class outer and that appropriate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
Which of the following is illegal statement? | float f=1.01;
What will happen when you compile and run the following code? public class Scope{ private int i; public static void main(String argv[]){ Scope s = new Scope(); s.amethod(); }//End of main public static void amethod(){ System.out.println(i); }//end of amethod }//End of class | a compile time error
Suppose class X contains the following method: | void dosomething(int a, float b){ ... }
Which line contains only legal statements? | string x = "hello", int y = 9; x = x + y;
Which of the following operations might throw an ArithmeticException? (select two) | % /
How do you prevent shared data from being corrupted in a multithreaded environment? | access the variables only via synchronized methods
Which of the following is true? | the >> operator carries the sign bit when shifting right. the >>> zero-fills bits that have been shifted out
Select the most correct statement: | a protected method may only be accessed by classes or interfaces of the same package or by subclasses of the class in which it is declared.
11. public inteface Status{ 12. /*insert code here*/ int MY_VALE = 10; 13. } Which three are valid in line 12? (select three) | final static public
Consider the following code: 1. Dog rover, fido; 2. Animal anim; 3. 4. rover = new Dog(); 5. anim = rover; 6. fido = (Dog)anim; Where: Mammal extends Animal Dog extends Mammel Which of the following statements is true? | the code will compile and run
You want to loop through an array and stop when you come to the last element. Being a good java programmer and forgetting everything you ever knew about C/C++ you know that arrays contain information about their size. Which of the following can you use? | myarray.length;
import java.awt.*; public class FlowAp extends Frame{ public static void main(String argv[]){     FlowAp fa=new FlowAp();     fa.setSize(400,300);     fa.setVisible(true);  }  FlowAp(){         add(new Button("One"));         add(new Button("Two"));         add(new Button("Three"));        add(new Button("Four"));     }//End of constructor    }//End of Application | a frame with one large button marked four in the centre
How do you indicate where a component will be positioned using Flowlayout? | do nothing, the flowlayout will position the component
How do you change the current layout manager for a container | use the setlayout method
Which of the following are fields of the GridBagConstraints class? | ipadx fill insets
import java.awt.*; public class CompLay extends Frame{ public static void main(String argv[]){     CompLay cl = new CompLay();     }  CompLay(){     Panel p = new Panel();     p.setBackground(Color.pink);     p.add(new Button("One"));     p.add(new Button("Two"));     p.add(new Button("Three"));     add("South",p);     setLayout(new FlowLayout());     setSize(300,300);     setVisible(true);     } } | the buttons will run from left to right along the top of the frame
Which statements are correct about the anchor field? | it is a field of the gridbagconstraints class for controlling component placement a valid settting for the anchor field is gridbagconstraints.north
Is the following statement true or false? When using the GridBagLayout manager, each new component requires a new instance of the GridBagConstraints class. | false
Which most closely matches a description of a Java Map? | an interface that ensures that implementing classes cannot contain duplicates
How does the set collection deal with duplicate elements? | the add method returns false if you attempt to add an element with a duplicate value
What can cause a thread to stop executing? | the program exits via a call to exit(0); the priority of another thread is increased a call to the stop method of the thread class
For a class defined inside a method, what rule governs access to the variables of the enclosing method? | the class can only access final variables
Under what circumstances might you use the yield method of the Thread class | to call from the currently running thread to allow another thread of the same or higher priority to run
public class Hope{     public static void main(String argv[]){ 	Hope h = new Hope();     }      protected Hope(){ 	for(int i =0; i <10; i ++){ 	    System.out.println(i); 	}     } } | compilation and running with output 0 to 9
public class MySwitch{ public static void main(String argv[]){     MySwitch ms= new MySwitch();     ms.amethod();     }   public void amethod(){     int k=10;          switch(k){          default: //Put the default at the bottom, not here             System.out.println("This is the default output");              break;           case 10:              System.out.println("ten");          case 20:              System.out.println("twenty");          break;         }     } } | none of these options
Which of the following is the correct syntax for suggesting that the JVM performs garbage collection | system.gc();
public class As{     int i = 10;     int j;     char z= 1;     boolean b;     public static void main(String argv[]){ 	As a = new As(); 	a.amethod();     }     public void amethod(){         System.out.println(j);         System.out.println(b);                     } } | compilation succeeds and at run time an output of 0 and false
public class Arg{ String[] MyArg;         public static void main(String argv[]){         MyArg=argv;         }          public void amethod(){                 System.out.println(argv[1]);         } } | compile time error
public class StrEq{ public static void main(String argv[]){         StrEq s = new StrEq();         }         private StrEq(){                 String s = "Marcus";                 String s2 = new String("Marcus");                 if(s == s2){                         System.out.println("we have a match");                         }else{                         System.out.println("Not equal");                 }        } } | output of "not equal"
Which of the following classes implement java.util.List? (Choose two.) | arraylist+stack
Which of the following classes implements a FIFO Queue?  (Choose one.) | linkedlist
Which of the following declarations are illegal? (Choose three.) | default string s;abstract double d;abstract final double hyperboliccosine();
Which of the following expressions are legal? (Choose two.) | int x = 6; if (!(x > 3)) {};int x = 6; x = ~x;
Which of the following expressions are legal? (Choose two.) | string x = "hello"; int y = 9; x += y;string x = "hello"; int y = 9; x = x + y;
Which of the following expressions results in a positive value in x? (Choose one.) | int x = –1; x = x >>> 5;
Which of the following interfaces does not allow duplicate objects?  (Choose one.) | set
Which of the following is not appropriate situations for assertions? (Choose one) | preconditions of a public method
Which of the following is true? (Choose one.) | none of the above
Which of the following is(are) true? (Choose one.) | all the above
Which of the following may appear on the right-hand side of an instanceof operator? (Choose two.) | a class+an interface
Which of the following may be declared final? (Choose two.) | classes+methods
Which of the following may be statically imported? (Choose two.) | static method names+ static field names
Which of the following may follow the static keyword? (Choose three.) | data+methods+code blocks enclosed in curly brackets
Which of the following may legally appear as the new type (between the parentheses) in a cast operation? (Choose one.) | all of the others
Which of the following may not be synchronized? (Choose one.) | classes
Which of the following may override a method whose signature is void xyz(float f)? (Choose two.) | void xyz(float f)+public void xyz(float f)
Which of the following methods in the Thread class are deprecated? (Choose one.) | suspend() and resume()
Which of the following operations might throw an ArithmeticException? (Choose one.) | none of these
Which of the following operations might throw an ArithmeticException? (Choose one.) | /
Which of the following operators can perform promotion on their operands? (Choose three.) | +,-,~
Which of the following restrictions apply to anonymous inner classes? (Choose one.) | they must be defined inside a code block.
Which of the following signatures are valid for the main() method entry point of an application? (Choose two.) | public static void main(string arg[]),public static void main(string[] args)
Which of the following statements about the wait() and notify() methods is true? (Choose one.) | the thread that calls wait() goes into the monitor’s pool of waiting threads.
Which of the following statements about threads is true? (Choose one.) | threads inherit their priority from their parent thread.
Which of the following statements are true? (Choose one.) | a final class may not be extended.
Which of the following statements are true? (Choose one.) | given that inner is a nonstatic class declared inside a public class outer and that appropriate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
Which of the following statements are true? (Choose one.) | none of the above
Which of the following statements are true? (Choose two.) | stringbuilder is generally faster than stringbuffer.stringbuffer is threadsafe; stringbuilder is not.
Which of the following statements are true?1)An abstract class may not have any final methods.2)A final class may not have any abstract methods. | only statement 2
Which of the following statements is true? (Choose one.) | transient variables are not serialized.
Which of the statements below are true? (Choose one.) | unicode characters are all 16 bits.
Which of the statements below are true? (Choose one.) | none of the above
Which of the statements below are true? (Choose one.) | none of the above.
Which one line in the following code will not compile?1. byte b = 5;2. char c = ‘5’;3. short s = 55;4. int i = 555;5. float f = 555.5f;6. b = s;7. i = c;8. if (f > b)9.      f = i; | line 6
Which one statement is always true about the following application?1. class HiPri extends Thread {2.       HiPri() {3.             setPriority(10);4.       }5.6.       public void run() {7.             System.out.println(8.                         "Another thread starting up.");9.             while (true) { }10.     }11.12.      public static void main(String args[]) {13.             HiPri hp1 = new HiPri();14.             HiPri hp2 = new HiPri();15.             HiPri hp3 = new HiPri();16.             hp1.start();17.             hp2.start();18.             hp3.start();19.       }20. } | none of the above scenarios can be guaranteed to happen in all cases.
Which one statement is true about the following code fragment? (choose 1)1. import java.lang.Math;2. Math myMath = new Math();3. System.out.println("cosine of 0.123 = " +  myMath.cos(0.123)); | compilation fails at line 2.
Which one statement is true about the following code fragment?1. String s = "FPT";2. StringBuffer s1 = new StringBuffer("FPT");3. if (s.equals(s1))4.      s1 = null;5. if (s1.equals(s))6.      s = null; | compilation succeeds. no exception is thrown during execution.
Which one statement is true about the following code?1. String s1 = "abc" + "def";2. String s2 = new String(s1);3. if (s1 == s2)4.      System.out.println("== succeeded");5. if (s1.equals(s2))6.      System.out.println(".equals() succeeded"); | line 6 executes and line 4 does not.
Which one statement is true concerning the following code?1. class Greebo extends java.util.Vector  implements Runnable {2.3.        public void run(String message) {4.                 System.out.println("in run() method: " +  message);5.6.         }7. }8.9. class GreeboTest {10.                 public static void main(String args[]) {12.                         Greebo g = new Greebo();13.                         Thread t = new Thread(g);14.                         t.start();15.                 }16. } | there will be a compiler error, because class greebo does not correctly implement the runnable interface.
Which statement is true about the following code fragment? (Choose one.)1. int j = 2;2. switch (j) {3.      case 2:4.           System.out.println("value is two");5.      case 2 + 1:6.           System.out.println("value is three");7.           break;8.      default:9.           System.out.println("value is " + j);10.         break;11. } | the output would be the text value is two followed by the text value is three.
Which statement is true about the following method?int selfXor(int i) {    return i ^ i;} | it always returns 0.
Which statement is true about this application? (Choose one.)1. class StaticStuff2 {3.      static int x = 10;4.5.      static { x += 5; }6.7.      public static void main(String args[])8.      {9.           System.out.println("x = " + x);10.    }11.12.    static {x /= 5; }13. } | the code compiles and execution produces the output x = 3.
Which statement is true about this code? (Choose one.)1. class HasStatic2. {3.       private static int x = 100;4.5.       public static void main(String args[])6.       {7.             HasStatic hs1 = new HasStatic();8.             hs1.x++;9.             HasStatic hs2 = new HasStatic();10.           hs2.x++;11.           hs1 = new HasStatic();12.           hs1.x++;13.           HasStatic.x++;14.           System.out.println("x = " + x);15.       }16. } | the program compiles and the output is x = 104.
Which statements about JDBC are NOT true? (choose 2) | jdbc is a java  database system.,jdbc is a java api for connecting to any kind of dbms
Which two code fragments correctly create and initialize a static array  of int elements? (Choose two.) | static final int[] a = { 100,200 };static final int[] a; static { a=new int[2]; a[0]=100; a[1]=200; }
Which two of the following interfaces are at the top of the hierarchies in the Java Collections Framework?  (Choose two.) | map+collection
You execute the following code in an empty directory. What is the result? (Choose one.)1. File f1 = new File("dirname");2. File f2 = new File(f1, "filename"); | no directory is created, and no file is created.
You have been given a design document for a veterinary registration system for implementation in Java. It states:"A pet has an owner, a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating if it has been neutered, and a textual description of its markings."Given that the Pet class has already been defined and you expect the Cat class to be used freely throughout the application, how would you make the opening declaration of the Cat class, upto but not including the first opening brace? Use only these words and spaces: boolean, Cat, class, Date, extends, Object, Owner, Pet, private, protected, public, String.(Choose one.) | public class cat extends pet
You have been given a design document for a veterinary registration system for implementation in Java. It states:"A pet has an owner, a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating whether it has been neutered, and a textual description of its markings."Given that the Pet class has already been defined, which of the following fields would be appropriate for inclusion in the Cat class as members? (Choose two.) | boolean neutered;string markings;
The defauft type of the Result et object | type_forward_only
Suppose the declared type of x is a class, and the declared type of y is an interface. When is the assignment x =y, legal? | when the type of x is object
In RMI implementations, all methods, declared in the remote interface, must throw the ...exception | remoteexception
Suppose salaries is an array containning floats. Which of the following are vaild loop control statements for processing each element of salaries? | for(int i:salaries)
How can you force garbage collection of an object | garbage collection cannot be forced
Which of the followings satement is true | flowlayout is the default layout manager for every jframe
static boolean b1=false; static int i = -1; static double d = 10.1; | b=m; d=i;
public class Abs extends Base { public static void main(String argv[]){ Abs a = new Abs(); a.amethod();} | the code will compile and run, printinh out the words
Which of the following statements is true about two base protocols used for networking TCP and UDP | tcp and udp are connection-based protocols
class in the primary class that has the driver information | drivermanager
Which of the following methods of the java.io.File can be used to create a newfile | creaenewfile()
Which of the following statements is INCORRECT about a non-static synchronized method | it cannot call to a static synchronized method of the current class
The Swing component classes can be found in the ________________ package. | javax.swing
This question concerns the following class definition:1. package abcde; 2. 3. public class Bird { 4.       protected static int referenceCount = 0; 5.       public Bird() { referenceCount++; } 6.       protected void fly() { /* Flap wings, etc. */ } 7.       static int getRefCount() { return referenceCount; } 8. } Which statement is true about class Bird and the following class Parrot? (Choose one.) 1. package abcde; 2. 3. class Parrot extends abcde.Bird { 4.       public void fly() { 5.             /* Parrot-specific flight code. */ 6.       } 7.       public int getRefCount() { 8.             return referenceCount; 9.       } 10. } | compilation of parrot.java fails at line 7 because method getrefcount()
This question concerns the following class definition: 1. package abcde; 2. 3. public class Bird { 4.      protected static int referenceCount = 0; 5.      public Bird() { referenceCount++; } 6.      protected void fly() { /* Flap wings, etc. */ } 7.      static int getRefCount() { return referenceCount; } 8. } Which statement is true about class Bird and the following class Nightingale? (Choose one.) 1. package singers; 2. 3. class Nightingale extends abcde.Bird { 4.      Nightingale() { referenceCount++; } 5. 6.      public static void main(String args[]) { 7.           System.out.print("Before: " + referenceCount); 8.           Nightingale florence = new Nightingale(); 9.           System.out.println(" After: " + referenceCount); 10.         florence.fly(); 11.     } 12. } | before: 0 after: 2.
This question involves IOException, AWTException, and EOFException. They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends OException. uppose class X contains the following method: void doSomething() throws IOException{ … }  Which of the following methods may appear in class Y, which extends X? (Choose three.) | void dosomething() { … }
This question involves IOException, AWTException, and EOFException. They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends OException. uppose class X contains the following method: void doSomething() throws IOException{ … }  Which of the following methods may appear in class Y, which extends X? (Choose three.) | void dosomething() throws eofexception { … }
This question involves IOException, AWTException, and EOFException. They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends OException. uppose class X contains the following method: void doSomething() throws IOException{ … }  Which of the following methods may appear in class Y, which extends X? (Choose three.) | void dosomething() throws ioexception, eofexception { … }
What are the legal types for whatsMyType? (Choose one.)  short s = 10; whatsMyType = !s; | there are no possible legal types.
What does the following code do? Integer i = null; if (i != null & i.intValue() == 5)      System.out.println("Value is 5"); | throws an exception.
What does the following code fragment print out at line 9? (Choose one.) 1. FileOutputStream fos = new FileOutputStream("xx"); 2. for (byte b=10; b<50; b++) 3.      fos.write(b); 4. fos.close(); 5. RandomAccessFile raf = new RandomAccessFile("xx", "r"); 6. raf.seek(10); 7. int i = raf.read(); 8. raf.close() 9. System.out.println(“i = “ + i); | the output is i = 20.
What does the following code print? public class A {       static int x;       public static void main(String[] args) {             A that1 = new A();             A that2 = new A();             that1.x = 5;             that2.x = 1000;             x = -1;             System.out.println(x);       } } | -1
What happens when you try to compile and run the following application? (Choose one.) 1. import java.io.*; 2. 3. public class Xxx { 4.      public static void main(String[] args) { 5.           try { 6.                File f = new File("xxx.ser"); 7.                FileOutputStream fos = new FileOutputStream(f); 8.                ObjectOutputStream oos = new ObjectOutputStream(fos); 9.                oos.writeObject(new Object()); 10.              oos.close(); 11.              fos.close(); 12.         } 13.        catch (Exception x) { } 14.    } 15. } | an exception is thrown at line 9.
What happens when you try to compile and run the following code? public class Q {       static String s;       public static void main(String[] args) {             System.out.println(">>" + s + "<<");       } } | the code compiles, and prints out >>null<<
What happens when you try to compile and run this application? (Choose one.)  1. import java.util.*; 2. 3. public class Apple { 4.      public static void main(String[] a) { 5.           Set<Apple> set = new TreeSet<Apple>(); 6.           set.add(new Apple()); 7.           set.add(new Apple()); 8.           set.add(new Apple()); 9.      } 10. } | an exception is thrown at line 7.
What is the difference between the rules for method-call conversion and the rules for assignment conversion? (Choose one.) | there is no difference; the rules are the same.
What is the minimal modification that will make this code compile correctly? (Choose one.) 1. final class Aaa 2. { 3.       int xxx; 4.       void yyy() { xxx = 1; } 5. } 6. 7. 8. class Bbb extends Aaa 9. { 10.       final Aaa finalref = new Aaa(); 11. 12.       final void yyy() 13.       { 14.             System.out.println("In method yyy()"); 15.             final ref.xxx = 12345; 16.       } 17. } | on line 1, remove the final modifier.
What is the range of values that can be assigned to a variable of type byte? (Choose one.) | -2^7 through 2^7 - 1
What is the range of values that can be assigned to a variable of type short? (Choose one.) | -2^15 through 2^15 - 1
What is the result of attempting to compile and execute the following code fragment? Assume that the code fragment is part of an application that has write permission in the current working directory. Also assume that before execution, the current working directory does not contain a file called datafile. (Choose one.)  1. try { 2.      RandomAccessFile raf = new 3.      RandomAccessFile("datafile" ,"rw"); 4.      BufferedOutputStream bos = new BufferedOutputStream(raf); 5.       6.      DataOutputStream dos = new DataOutputStream(bos); 7.       8.      dos.writeDouble(Math.PI); 9.      dos.close(); 10.    bos.close(); 11.   raf.close(); 12. } 13. catch (IOException e) { } | the code fails to compile.
What is the return type of the instanceof operator? | a boolean
What method of the java.io.File class can create a file on the hard drive? (Choose one.) | createnewfile()
What results from attempting to compile and run the following code? 1. public class Conditional { 2.       public static void main(String args[]) { 3.             int x = 4; 4.             System.out.println("value is " +  ((x > 4) ? 99.99 : 9)); 5.       } 6. } | the output: value is 9.0
What results from running the following code? 1. public class Xor { 2.       public static void main(String args[]) { 3.             byte b = 10; // 00001010 binary 4.             byte c = 15; // 00001111 binary 5.             b = (byte)(b ^ c); 6.             System.out.println("b contains " + b); 7.       } 8. } | the output: b contains 5
What would be the output from this code fragment?  1. int x = 0, y = 4, z = 5; 2. if (x > 2) { 3.      if (y < 5) { 4.           System.out.println("message one"); 5.      } 6.      else { 7.           System.out.println("message two"); 8.      } 9. } 10. else if (z > 5) { 11.      System.out.println("message three"); 12. } 13. else { 14.      System.out.println("message four"); 15. } | message four
When comparing java.io.BufferedWriter to java.io.FileWriter, which capability exists as a method in only one of the two?  (Choose one.) | writing a line separator to the stream
When does an exception's stack trace get recorded in the exception object? (Choose one.) | when the exception is constructed
When is it appropriate to pass a cause to an exception's constructor? (Choose one.) | when the exception is being thrown in response to catching of a different exception type
When is it appropriate to write code that constructs and throws an error? (Choose one.) | never
When is x & y an int? (Choose one) | sometimes
When the user attempts to close the frame window, _______ event in generated. | window closing
When the user selects a menu item, _______ event is generated. | action event
When you compile a program written in the Java programming language, the compiler converts the human-readable source file into platform-independent code that a Java Virtual Machine can understand. What is this platform-independent code called? | bytecode
Whenever a method does not want to handle exceptions using the try block, the ________ is used. | throws
Which are the correct statements used for getting connection object to connect to SQL Server database? | string url ="jdbc:odbc:data_source_name";
Which class and static method can you use to convert an array to a List?  (Choose one.) | arrays.aslist
Which is four-step approach to help you organize your GUI thinking. (Choose one.) | identify needed components isolate regions of behavior.
Which is the four steps are used in working with JDBC? | 1)connect to the database
Which JDBC processing model  that requires a JDBC driver that can communicate with the particular data source being accessed? | two-tier
Which line of code tells a scanner called sc to use a single digit as a delimiter? (Choose one.) | sc.usedelimiter("\\d");
Which Man class properly represents the relationship "Man has the best friend who is a Dog"? (Choose one.) | class man { private dog bestfriend; }
Which methods return an enum constant’s name? (Choose two.) | name() tostring()
Which of the following are legal argument types for a switch statement? (Choose three.) | byte int char
Which of the following are legal enums? (Choose three.) | enum animals { lion, tiger, bear }
Which of the following are legal enums? (Choose three.) | enum animals { lion, tiger, bear; int weight;}
Which of the following are legal enums? (Choose three.) | enum animals { lion(450), tiger(450), bear; int weight; animals() { } animals(int w) {weight = w;}}
Which of the following are legal import statements? (Choose two.) | import java.util.vector; import static java.util.vector.*;
Which of the following are legal loop constructions? (Choose one.) | int j = 0; for
Which of the following are legal loop definitions? (Choose one.) | none of the above
Which of the following are legal? (Choose three.) | for (int i=0, j=1; i<10; i++, j++)
Which of the following are legal? (Choose three.) | for (int i=0, j=1;; i++, j++)
Which of the following are legal? (Choose three.) | for (string s = ""; s.length()<10; s += '!')
Which of the following are legal? (Choose two.) | double d = 1.2d;
Which of the following are legal? (Choose two.) | int c = 0xabcd;
Which of the following are legal? (Choose two.) | int d = 0xabcd;
Which of the following are legal? (Choose two.) | char c = 0x1234;
Which of the following are legal? (Choose two.) | char c = '\u1234';
Which of the following are legal? (Choose two.) | <string>()
Which of the following are methods of the java.util.SortedMap interface? (Choose three.) | map
Which of the following are methods of the java.util.SortedSet interface? (Choose one.) | all the above
Which of the following are true? (Choose one.) | all the above
Which of the following are true? (Choose one.) | the jvm runs until there are no non-daemon threads.
Which of the following are true? (Choose three.) | when an application begins running, there is one non-daemon thread, whose job is to execute main().
Which of the following are true? (Choose three.) | a thread created by a daemon thread is initially also a daemon thread.
Which of the following are true? (Choose three.) | a thread created by a non-daemon thread is initially also a non-daemon thread
Which of the following are true? (Choose two.) | when you declare a method  ... object
Which of the following are true? (Choose two.) | when you declare a block  ... synchronize
Which of the following are true? (Choose two.) | an enum may contain public method definitions
Which of the following are true? (Choose two.) | an enum may contain private data
Which of the following are true? (Choose two.) | primitives are passed by value.
Which of the following are true? (Choose two.) | references are passed by value.
Which of the following are true? (Choose two.) | an anonymous inner class may implement at most one interface.
Which of the following are true? (Choose two.) | an anonymous inner class may extend a parent class other than object.
The readLine() method of the RandomAccessFile class return false when it has reached the end of a file  The readLine() method of the RandomAccessFile class return null when it has reached the end of a file The readLine() method of the RandomAccessFile class return true when it has reached the end of a file | return false
The container can display three completely different components at different times, depending perhaps on user input or program state. Even if the components' sizes differ. switching from one component to the next shouldn't change the amount of space devoted to the component. | gridlayout
Assuming any exception handling has been set up, which of the following will create an instance of the RandomAccessFile class? | ("myfile.txt","rw")
Which of the following statements is INCORRECT about a non-static synchronized method? | it cannot call to a static synchronized
Which of the following statements is true about two base protocols used for networking: TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) | tcp is a connection-based
Which of the following statements about this code is true? public class Morecombe{ public static void main(String argva)( Morecombe m = new MorecombeQ; m.go(new TuringQ{}); } public void go(Turing t){ t.start(): } } class Turing extends Thread{ public void run(){ for(int i =0: i < 2: i++){ System.out.println(i): } } } | compilation and output of 0 followed by 1
Which of the following collections supports accessing elements through keys and values? | hashset
What is the difference between a TextArea and a TextField? | textareas are used for displaying graphics
What will be output if you try to compile and run the following code, but there is no file called Hello.bct in the current directory?. import java.io.*: public class Mine ( public static void main(String argv0){ Mine m=new Mine(); System.out.println(m.amethod()); } public int amethod() ( try{ FilelnputStream dis=new FilelnputStream("Hello.bd"); }catch (FileNotFoundException fne) { System.outprintln("No such file found"); return -1; }catch(10Exception ioe) { } finally{ System.out.println("Doing finally"); } return 0; | no such file found, doing finally, -1
What will happen when you attempt to compile and run the following code? public class Main{ A ? A public static void main(String argv0){ At= new A("One"); ? B trump; A h = new A("Two"); ? C limn(); ? D } } class A extends Thread{ private String sTname=""; A(String s){ sTname = s; I Ned I 1 public void rump{ for(int i =0; i <2: i-){ try{ sleep(1000); }catch(InterruptedException e){} yield(); System.outprint(sTname + ""); } } } | output one two one two
Which of the following statements is true? | the client knows the hostname of the machine on which the server is running and the port number on which the server is listening
What is the output when you try to compile and run the following program? ? A public class Main{ static void foo(String x) {System.out.println("String");} 1:1 B static void foo(StringBuffer y) {System.outprintln("StringBuffer);} static void foo(Integer z) {System.outprintInrInteger");} ? C public static void main(String argv0){ f(null): ? D System.outprintinQ; ? | no output compile-time error
Which of the followings statements is true? | gridlayout simply makes a bunch of components equal in size and displays them in the requested number of rows and columns
Answer RMI applications often comprise two separate programs. a server and a client and they | must run in two separate computers
How can you change the current working directory using an instance of the File class called FileName? | the file class does not support directly changing the current directory
What happens when you try to compile and run the following program? A D A import java.util.*; B public class Main{ public static void main(String argv[]){ D c Vector<lnteger> t = new Vector<lnteger>(); t.add(12r; D D t.add(2); t.add(6); t.add(2.4); lterator<lnteger> i = t.iterator(); int sum=0; Next while(i.hasNext()) sum += i.next(); System.out.println(sum); | the program has a compile error
Select correct statement(s): (choose one option) (1) A thread can be an instance of the java.lang.Thread class. D A (2) A thread can be an instance of a subclass of the java.lang.Thread class. D B (3) An instance of a class which implements the java.lang.Runnable can supply the executable code for a thread object. | 1 2 3
The default type of the ResultSet object is  : | type_forward_only
What will be output when the following code is run? class Test 0 A {public int fun(intx) {int count=1; D 3 try{ count += )c [I C foo(count); count++z D D }catch(Exception e) { count 0: )c} return(count); D E public int foo(int k) {if(true) throw new ArithmeticExceptionO;  return(k); Next  class Main {public static void main(String [] args)  {Testt = new TestO: System.out.println(t.fun(2)); | 1
Which of the following statements is true? | a for state ent can loop infinitely, for example: for(;;)
Which of the following most closely describes the process of overriding? | a method with the same name but different parameters
Fill the blanks: (1) The java.io. class makes it easier to write platform-independent code that examines and manipulates files. D A (2) The Java.io. class makes it easier to write platform-independent code that examines and manipulates folders. | file, file
What interfaces can be implemented in order to create a class that can be serialized? | implements java.io.serializable, which defines two methods: readobject and writeobject
Answer Select correct statement: E] | both string and stringbuffer objects are not constants.
What is the output when you try to compile and run the following program? public class Main{ public static void main(String argvfl){ String s = "Hi there"; int pos = s.indexof(" ")1 String r= s.substring(0. pos): String s2 = new String(new char[] {'H'.'i'}): if(r.equals(s2)) System.out.println("EQUAL"): else System.outprintln("NOT EQUAL"):  System.out.println(): | not equal
Which of the following modifiers does not allow a variable to be modified its value once it was initialized? | final
Which is the first step of four-step approach to help you organize your GUI thinking? | identify needed components.
What will happen when you attempt to compile and run the following code? class Base{ Base(){ System.out.println("Base");  public class Checket extends Base{ public static void main(String argv[]){ Checket c = new ChecketO; super();  Checketo{ Systemoutprintln("Checket"); | runtime error
With respect to networking and the client-server model.  (1) A socket is one endpoint (a combination of an IP address and a port number) of a two-way communication link between two programs running on the network..  (2) TOP (Transmission Control Protocol) is a connection o based protocol that provides a reliable flow ofdata between two computers.  (3) UDP (User Datagram Protocol) is a protocol that sends independent packets of data. called datagrams. from one computer to another with no guarantees about arrival. | true. true. true
Which of the following is NOT an example of a data type. | button
Which of the following is true? | the iterator interface is used to step through the elements of a collection
What will happen when you compile and run the following code? public class Scope{ private int i; public static void main(String argv[]){ Scope s = new ScopeO: s.amethodo:  End of main public static void amethodo{ System.out.println(i); end of a method End of class | a compile time error
Which statement is true of the following code?  10. public class Agg{  11. public static void main(String argvfl){  12. A99 a = new A990:  13. a.go():  14.  15. public void goO{  16. DSRoss ds1 = new DSRoss("one"); 17. ds1.starto:   18.  19.  20. class DSRoss extends Thread{  21. private String sTname="":  22. DSRoss(String s){  23. sTname = s: | runtime error. an exception will be thrown
What will happen when you attempt to compile and run the following code? public class Agg{ static public long i=10; public static void main(String argv[]){ switch(i){  default  System.out.println("no value given");  case 1:  System.out.println("one");  case 10:  System.outprintln("ten");  case 5:  System.outprintln("five"): | compile time error
Which of the following statements is true? | to be overriden method must have the same name. parameter and return types
With respect to JDBC. which statement is NOT CORRECT? | in the three-tier model. a "middle tier" of services is let
Which of the following statements is true? | interfaces are the java approach to addressing
Select an incorrect identifier in Java. | &x
Consider the following code developed in NetBeans. What does the thread t do? | it wiii show a full of formatted current date in the jlabei1
Which of the following is a method of the Runnable interface? | run
Which of the following is valid method? | static native void amethod
Select an operation which may cause an unchecked exception. | controiiing the state of a running thread
Which of the following is true? | an enum may contain public method definitions.
Which of the following layout manager will present components with the same size. | java.awt.gridlayout
What will happen when you attempt to compile and run the following program: 10. abstract class A{  11. int x=5:  12. void foo()  13. System.out.print("x = " + x);  14.  15.  16. class Main   17. static void foo(lnteger x){  18. System.out.print(x);  19.  20. public static void main(String[] args){ 21. At: newAo{  22. public void fooO{  23. System.outprint("Hello");  24.   25.  26. tfooO:   27.  28. | the output is hello
What will happen when you attempt to compile and run the following code int Output=10: boolean b1 =false: if((b1==true) 8.8. ((Output+=10)==20)){ System.out.println("We are equal "+Output); else  System.out.println("Not equal! "+Output); | compilation and output of "not equal! 10"
is applied in a class. is applied in a class hierarchy. | method generalization. method specification
What will happen when you attempt to compile and run the following code import java.io.*;class Base{    public void amethod()throws FileNotFoundException{}}public class ExcepDemo extends Base{    public static void main(String argv[]){	ExcepDemo e = new ExcepDemo();    }    public void amethod(){}    protected ExcepDemo(){	try{	    DataInputStream din = new DataInputStream(System.in);	    System.out.println("Pausing");	    din.readByte();	    System.out.println("Continuing");	    this.amethod();	}catch(IOException ioe) {}    }} | compile and run with output of "pausing" and "continuing" after a key is hit
What will happen when you attempt to compile and run this programpublic class Outer{public String name = "Outer";public static void main(String argv[]){        Inner i = new Inner();        i.showName();    }//End of main        private class Inner{        String name =new String("Inner");                void showName(){                        System.out.println(name);                }        }//End of Inner class} | compile time error because of the line creating the instance of inner
What will happen when you attempt to compile and run this code//Demonstration of event handling import java.awt.*;import java.awt.event.*;public class MyWc extends Frame implements WindowListener{public static void main(String argv[]){        MyWc mwc = new MyWc();        }        public void windowClosing(WindowEvent we){                System.exit(0);                }//End of windowClosing      public void  MyWc(){        setSize(300,300);        setVisible(true);        }}//End of class | error at compile time
Which option most fully describes will happen when you attempt to compile and run the following code public class MyAr{    public static void main(String argv[]) {        MyAr m = new MyAr();        m.amethod();    }    public void amethod(){        static int i;        System.out.println(i);    }} | compile time error
Which of the following will compile correctly | int z = 015;
Which of the following are Java key words | double + instanceof
What will be output by the following line?System.out.println(Math.floor(-2.1)); | -3.0
Given the following main method in a class called Cycle and a command line ofjava Cycle one twowhat will be output?public static void main(String bicycle[]){        System.out.println(bicycle[0]);} | one
Which of the following statements are true? | the set is designed for unique elements.
Which of the following statements are correct? | if multiple listeners are added to a component the events will be processed for all but with no guarantee in the order,you may remove as well add listeners to a component.
Given the following code class Base{}public class MyCast extends Base{    static boolean b1=false;    static int i = -1;    static double d = 10.1;    public static void main(String argv[]){        MyCast m = new MyCast();        Base b = new Base();        //Here    }}Which of the following, if inserted at the comment //Here will allow the code to compile and run without error | 1) b=m;3) d =i;
Which of the following statements about threading are true | you can obtain a mutually exclusive lock on any object, a thread can obtain a mutually exclusive lock on an object by calling a synchronized method on that object. ,thread scheduling algorithms are platform dependent
Your chief Software designer has shown you a sketch of the new Computer parts system she is about to create. At the top of the hierarchy is a Class called Computer and under this are two child classes. One is called LinuxPC and one is called WindowsPC.The main difference between the two is that one runs the Linux operating System and the other runs the Windows System (of course another difference is that one needs constant re-booting and the other runs reliably). Under the WindowsPC are two Sub classes one called Server and one Called Workstation. How might you appraise your designers work? | ask for a re-design of the hierarchy with changing the operating system to a field rather than class type
Which of the following statements are true | an inner class may be defined as static + an inner class may extend another class
What will happen when you attempt to compile and run the following code int Output=10;boolean b1 = false;if((b1==true) && ((Output+=10)==20)){    System.out.println("We are equal "+Output);    }else    {    System.out.println("Not equal! "+Output);} | compilation and output of "not equal! 10"
Given the following variables which of the following lines will compile without error?String s = "Hello";long l = 99;double d = 1.11;int i = 1;int j = 0;1) j= i <<s;2) j= i<<j;3) j=i<<d;4)j=i<<l; | j= i<<j;j=i<<l;
What will be output by the following line of code?System.out.println(010 | 4);  |  12
Given the following variables char c = 'c';int i = 10;double d = 10;long l = 1;String s = "Hello";Which of the following will compile without error? | s+=i;
Which of the following will compile without error? | file f = new file("/","autoexec.bat");datainputstream d = new datainputstream(system.in);outputstreamwriter o = new outputstreamwriter(system.out);
Given the following classes which of the following will compile without error?interface IFace{}class CFace implements IFace{}class Base{}public class ObRef extends Base{    public static void main(String argv[]){        ObRef ob = new ObRef();        Base b = new Base();        Object o1 = new Object();        IFace o2 = new CFace();    }} | o1=o2;b=ob;o1=b;
Given the following code what will be the output?class ValHold{        public int i = 10;}public class ObParm{public static void main(String argv[]){        ObParm o = new ObParm();        o.amethod();        }        public void amethod(){                int i = 99;                ValHold v = new ValHold();                v.i=30;                another(v,i);                System.out.print( v.i );        }//End of amethod        public void another(ValHold v, int i){                i=0;                v.i = 20;                ValHold vh = new ValHold();                v =  vh;                System.out.print(v.i);        System.out.print(i);        }//End of another} | 10020
Given the following class definition, which of the following methods could be legally placed after the comment//Here public class Rid{        public void amethod(int i, String s){}        //Here} | public void amethod(string s, int i){} +  public void amethod(int i, string s) {}
Given the following class definition which of the following can be legally placed after the comment line//Here ?class Base{public Base(int i){}}public class MyOver extends Base{public static void main(String arg[]){                MyOver m = new MyOver(10);                }        MyOver(int i){                super(i);        }        MyOver(String s, int i){                this(i);                 //Here        }} | base b = new base(10);
Given the following class definition, which of the following statements would be legal after the comment //Here class InOut{String s= new String("Between");        public void amethod(final int iArgs){       int iam;              class Bicycle{                       public void sayHello(){                        //Here                        }                }//End of bicycle class        }//End of amethod       public void another(){       int iOther;       }} | system.out.println(s);system.out.println(iargs);
Which of the following are methods of the Thread class? | yield()+sleep+stop()
Which of the following methods are members of the Vector class and allow you to input a new element | addelement
Which of the following statements are true? | a inner class may under some circumstances be defined with the protected modifier + an interface cannot be instantiated
Which of the following are correct event handling methods | mousepressed(mouseevent e){} + componentadded(containerevent e){}
Which of the following are methods of the Collection interface? | iterator + isempty + toarray
... exist within a ... Every ... has at least one... | threads, process, process, thread
Multithreaded execution is an essential feature of the Java platform. Every application has at least ... thread(s). | none of the others
An application that creates an instance of Thread must provide the code that will run in that thread. Select a correct way to do this. | provide a runnable object. the runnable object is passed to the thread constructor.
if an object is visible to more than one thread, all reads or writes to that object's variables should be done through ... methods. | none of the others
Select correct statement(s).(1) A process has a self-contained execution environment.(2) A sub-thread has a self-contained execution environment.(3) Programmers can schedule sub-threads of a program. | 1
Two sub-threads of a program may not need synchronized if …… | they do not access any common resource.
(1) An object having synchronized methods is called a( an ) ……….(2) The ……… technique can be applied with a hope that a deadlock situation may not occur in a program .(3) The sleep(… ) method of the java.lang.Thread class accepts a argument that specifies a( an ) …………. | monitor, wait-notify, specific period of time.
As soon as a Java thread is created, it enters the …….. state. | ready
Thread synchronization should be implemented if ..... | threads access common resources.
Which of the following statements is correct about Thread? | during its lifetime, a thread spends some time executing and some time in any of non-executing states.
Which of the following statement is correct about Thread? | when the run() method of a thread returns, that thread is put into ready state.
Which method is NOT a member the Object class? | waitall()
When a thread begins waiting an IO operation, it enters the ….. state. | blocked
In multi-processing system, | each process usually accesses its own data.
_____ exist within a ____ - every _____ has at least one. | theads, process, process.
Multithreaded execution is an essential feature of the Java platform. Every application has at least _____ thread(s). | one
if an object is visible to more than one thread, all reads or writes to that object's variables should be done through ____ methods. | synchronized
Select a correct statement. | deadlock describes a situation where two or more threads are blocked forever, waiting for each other.
Which of the following statements is true? | a thread must obtain the lock of the object it is trying to invoke a synchronized method.
Which of the following methods causes a thread to release the lock of the object that it is currently holding? | wait()
The muti-threaded programming is used ……. | when some tasks must be performed concurrently.
The muti-threaded programming is used ……. | when a task must be performed at un-predictable time.
Race condition may happen when: | more than one threads access the shared data of the application.
To create a thread in Java, we can: | create a subclass of the java.lang.thread class and override the method run().
Select correct priority values of a thread (Integer values only): | from 1 to 10
Which of the following options is not a thread state? | indelayed
With respect to threads in Java, select a correct statement. | the main method (entry point of a java program) is a default thread.
if an object may be accessed by some threads. These accesses should be done through ____ methods. | synchronized
Select the best choice. | deadlock describes a situation where two or more threads are blocked forever, waiting for each other.
Race condition may happen if: | there is more than one threads access the shared data of the application.
Which of the following options is not a valid thread priority property? | average_priority
When is a thread considered as a dead thread? | when the run() method terminates.
When is a thread started running? | the scheduler decides when a thread is started running.
The Java Collection framework is implemented in the ...package. | none of the others.
In order to use the TreeSet class, the class that describes elements must implement the ... interface. | java.lang.comparable
All of the numeric wrapper classes in the java.lang package are subclasses of the abstract class ... | java.lang.number
String S= "Hello"; String S2= new String("Java Program"); The String class describes an immutable chain of Unicode characters. Select a statement that causes an error. | none of the others.
Study the following code was implemented in the Hello class:static void print(Integer obj){ System.out.println(obj); } And it is used as:Integer obj= new Integer(5); int n= obj;  //(1) Hello.print( n );   //(2) A ….. operation is carried out at the code line (1)A ….. operation is carried out at the code line (2) | unboxing, boxing
The top interface of the Java Collection Framework is……. | collection
If we want to store a group of different elements in ascending order, the java.util.… class should be used. | sortedset
An instance of the java.util.Scanner class can read data from the keyboard (1), a file (2), a string of characters (3).(1) is ……., (2) is ……., and (3) is ……….. | true, true, true
Given a string constructed by calling s = new String( "xyzzy" ), which of the calls modifies the string? (Choose one.) | none of the others.
Which one statement is true about the following code?1. String s1 = "abc" + "def";2. String s2 = new String(s1);3. if (s1 == s2)4. System.out.println("== succeeded");5. if (s1.equals(s2))6. System.out.println(".equals() succeeded"); | line 6 executes and line 4 does not.
Which one statement is true about the following code fragment? (choose 1)1. import java.lang.Math;2. Math myMath = new Math();3. System.out.println("cosine of 0.123 = " + myMath.cos( 0.123 ) ); | compilation fails at line 2.
Suppose prim is an int and wrapped is an Integer. Which of the following are legal Java statements? (Choose one.)  prim = wrapped; wrapped = prim;prim = new Integer( 9 ); wrapped = 9; | all the others.
Suppose that obj1 and obj2 are objects and they belong to the same class. Study the semantics of following statements: (1) if (obj1==obj2) { } (2) if (obj1.equals( obj2 )) { } | (1) and (2) are different.
A characteristic of generic technique is ...... | it adds stability to the code by making more of bugs detectable at compile time.
Suppose that obj1 and obj2 are reference variables. The expression obj1==obj2 will execute …… | a swallow comparison.
One of the difference about Lists and Sets: | a list can contain duplicate items but a set can not.
Study the following Java statements: String s1= “Hello”; String s2= “Hello”; String s3= “Hello”; | there is only one string is stored in memory of the program.
Study the following Java statements: String S= “William, Bill is ill.”; int index1= S.indexOf(“ill”); int index2= S.lastIndexOf(“ill”); The value of index1 is ….. and index2 is …… | 1, 17
To traverse elements in a set, one after one element, the java.util.…….interface must be use | iterator
The _____ class is the ultimate ancestor of all Java classes. | object
The Java Collection framework is implemented in the ______ package. | java.util
In order to use the TreeSet class, the class that describes elements must implement the ______ interface. | java.lang.comparable
All of the numeric wrapper classes are subclasses of the abstract class ______. | number
String S= “Hello”;String S2= new String(“Hello”);The String class describes an immutable chain of Unicode characters. Select a statement that causes an error. | none of the others.
When invoking Math.random(), which of the following options might be the result? | the result is less than 1.0
Which of the following statements is true about Object class? | by default, the equals() method simply performs the == operator
Suppose that:- Your application has to read and write a string a lot of times. -Your application does not need to have multi threaded supports.- Performance is important.Which of the following classes will you choose to deal with string data type to achieve the above requirements? | stringbuilder
Suppose that a homogenous collection of objects, that belong the same type, are managed. Which of the following delarations is the best choice? | java.util.arraylist list;
Which of the following options is correct? | values stored in treeset are not allowed duplication
Which of the following options is not a method of the Scanner class? | nextvalue()
Which of the following collection cannot be used with Iterator class to traverse through elements? | array
Which of the following options is not a method of java.lang.Math Class? | none of the others
Which of the following classes is the ultimate ancestor of all Java classes? | none of the others
In Java Collection framework, which of the following pre-defined classes allow an element can be accessed through its index? | java.util.arraylist
In which situation are generic collections used? | the collection contains homogenous elements.
Which of the following Java lists that allows data is stored in sorted order, and also, no duplicate data is allowed? | treeset
You are required to build a Java application. Your application uses Vector to store data. Each time elements, taken from the vector, should be displayed to users in a random order. Which of the following methods can be used to achieve the above task? | collections.shuffle()
You are required to validate an email string taken from users. A valid email form should be email@address.com. Select a correct pattern that can be used to validate email input: | "^\w+@\w+[.]\w+$"
If we use Math.random() method to random a number, which of the following numbers will never be appeared? | 1.0
An I/O Stream represents an input source or an output destination. A stream can represent... | an i/o stream represents an input source or an output destination. a stream can represent...
The java.io.ObjectInputStream class is a subclass of the ...class. | java.io.inputstream
DataInputStream, DataOutputStream are binary streams, PrintWriter, BufferedReader are not binary streams ,ObjectInputStream, ObjectOutputStream are not text streams. | all of the others.
When reading objects from an object stream, | we usually use an explicit casting.
Select correct statement(s). (1) All byte stream classes are descended from the InputStream andOutputStream classes . (2) All character stream classes are descended from the Reader and Writer classes . (3) All byte stream classes are descended from the Reader and Writer classes .(4) All character stream classes are descended from the InputStream andOutputStream classes . | 1, 2
To read data from a text file using the line-by-line accessing. The right order of object creations is: | file – filereader - bufferedreader
To write objects to an object file. The right order of object creations is: | fileoutputstream- objectoutputstream
(1) The java.io…. class makes it easier to write platform-independent code that examines and manipulates files. (2) The java.io.…. class makes it easier to write platform-independent code that examines and manipulates folders. | file, file
Which of the following is true? (Choose one.) Readers have methods that can read and return floats and doubles. Readers have methods that can read and return floats. Readers have methods that can read and return doubles. | none of the others
Given the following class: public class Xyz implements java.io.Serializable { public int iAmPublic ; private int iAmPrivate ; static int iAmStatic ;  transient int iAmTransient ;  } Assuming the class does not perform custom serialization, which fields are written when an instance of Xyz is serialized? | iampublic, iamprivate
Which of the following are true? System.out has a println() method. System.out has a format() method.System.err has a println() method.System.err has a format () method. | all of the others.
When we access a file or directory metadata such as name, path, last modified time,… We should use the ........... class. | java.io.file
Suppose that you want reading some records stored in a text file, classes in the java.io package can be used:  (1) File, (2) FileInputStream, (3) RandomAccessFile,  (4) FileReader (5) BufferedReader, (6) PrintWriter | (1), (4), (5)
Consider the following declaration:  RandomAccessFile(File file, String mode)  If the mode is declared as “rws”, what does it mean? | it means the file can be opened for both reading and writing, and any changes to the file’s content or metadata will take place immediately.
Two topmost abstract classes for character streams are …... and ……. | java.io.reader, java.io.writer
The ……. class makes utilities to write platform-independent code that examines and manipulates folders. | java.io.file
To read/write objects from/to a file as object streams, the class declaration of these objects must implement the marker interface ….. | java.io.serializable
An I/O Stream represents an input source or an output destination. A stream can represent | all of the others
In _____ binary streams, a read/write data unit is _______. | low-level, general-format data
The ObjectInputStream is a subclass of the _____ class. | inputstream
Select a correct statement.DataInputStream, DataOutputStream are binary streams. PrintWriter, BufferedReader are text streams. ObjectInputStream, ObjectOutputStream are binary streams. | all of the others.
When reading objects from an object stream, we usually use _____. | an explicit class casting
Which of the following options is not a valid declaration of the RandomAccessFileclass? | randomaccessfile r = new randomaccessfile(“file.txt”, “w”);
In order to allow an object can be serialized into a file, which of the following interfaces needs to be implemented? | java.io.serializable
You are required to write a program that stores data retrieved from users to a text file. The data must be stored line by line and in Unicode format. Which of the following classes is the best choice for storing tasks? | java.io.printwriter
Which of the following classes is not an abstract class? | none of the others.
We have the constructor of the java.io.RandomAccessFile class as follows:  RandomAccessFile(String file, String mode) Which of the following options is not a valid value for the mode option? | “w”
Which of the following classes do not directly read from/write to input/output devices such as disk files or sockets; rather, they read from/write to other streams? | datainputstream/ dataoutputstream
Which of the following classes can be used to serialize an object into a file? | objectoutputstream
Which of the following methods of the File class can be used to get the size of a given file? | length()
A stream can represent …. | all of the others.
The ObjectInputStream is a subclass of the ………. class. | none of the other.
When accessing objects in an object stream, we must ……. | access them using a suitable program.
Which of the following features is not supported by java.io.RandomAccessFile class? | reading and writing data from and to a socket
You use java.io.RandomAccessFile to manipulate a file name myFile.txt. Which of the following statements is valid if you want to open the file myFile.txt in a writing-only mode? | there is no writing-only mode in java.io.randomaccessfile class.
Which of the following classes are exclusively designed for writing and reading Unicode characters? | filereader/ filewriter
Which of the following classes can be used for writing and reading objects (serializing/de-serializing) from and to a file? | objectinputstream/objectoutputstream
Which method do you use to enable or disable components such as JButtons? | none of the others
A component that lets the user pick a color. | jcolorchooser
The container has one component that should take up as much space as possible. Which layouts that easily deal with this situation should be selected? | gridlayout
Select correct statement(s). (1) Swing is part of the Java Foundation Classes and provides a rich set of GUI components. (2) Before you think about what your GUI will look like , it’s important to think about what it will | 1, 2
Select correct statement(s).(1) The Swing's list component (JList) can display text only. (2) The Swing’s button (JButton) can not contain an image. (3) The Swing’s label (JLabel) can present an image. | 3
Select correct statement(s). (1) 12 buttons can not be added to a container which is assigned to a grid layout 2x5.(2) If 2 components are added to the center region of a border-layout container, they will be seen by user as side-by-side components. | none of the others.
Which is four-step approach to help you organize your GUI thinking. (Choose one.) | identify needed components. isolate regions of behavior. sketch the gui. choose layout managers
The container can display three completely different components at different times, depending perhaps on user input or program state. Even if the components’ sizes differ, switching from one component to the next shouldn’t change the amount of space devoted to the component. | cardlayout
Select incorrect statement about FlowLayout. (choose 1) | it is the default layout manager type for jframe.
In a complex GUI containing a lot of components and user must be select some data in a group of specific data, the component should be used is ....... | combo box
We can replace a card layout of a container with .......... | tabbed pane
Select an incorrect statement. | a combobox can contain strings only.
In Swing, what is the role of the component’s model? | it is responsible for the data that the component presents to the users.
Suppose that we have a combobox that contains a list of data. The combobox can only display to the user one item at a time. In term of Model-View-Controller, which of the following statement is correct? | the list of data of the combobox can be considered as a representative of the model.
Which of the following statements is correct about Flow layout? | the flow layout arranges frames in horizontal rows.
Which of the following statement is correct about Card layout? | card layout arranges components in time rather than in space.
Which method do you use to enable and disable components such as JButton s? | setenable
A component that lets the user pick a color. | color chooser
The container has one component that should take up as much space as possible. Which layouts that easily deal with this situation should be selected? | borderlayout or gridlayout
The container has a row of components that should all be displayed at the same size, filling the container’s entire area. Which layout is the best choice for this purpose? | gridlayout
A component that displays an icon, but that doesn’t react to user clicks | label
In JTree control, which of the following classes represents for one node? | defaultmutabletreenode
Which of the following layout managers will make all its components the same size? | gridlayout
You are required to build a GUI application. The application has a main window which displays: - A tool bar at the top - A status bar at the bottom - A menu on the left - An information table on the right - A news board at the middle of the window Which of the following layout managers would you choose to achieve the above tasks? | borderlayout
Suppose that the layout of the frame f is BorderLayout. Study the following statement:g.getContentPane().add ( new JButton(“B”)); The button B will be let at the …. region of the frame. | none of the others.
Suppose you are building an application that connects to the database to store and retreive data. Your application is built based on Model-View-Controller pattern.  Which of the following components is responsible for connecting to the database? | •	 model.
Which of the following options is a method that you need to override when implementing the ActionListener interface? | actionperformed()
You are building a table model class that extends the AbstractTableModel class. Which of the following methods is not required to re-implement? | getcolumnname()
Which of the following statements is not correct about JTree control? | leaf nodes are those that can have children.
Leaf nodes are those that can have children. | textfield.requestfocus()
A swing container that groups some common components in a complex GUI. | •	 jpanel
To make the background color of a label different with the color of its container, we need to use the ….. method of the JLabel class first. | setopaque(true)
The default layout manager used by JPanel is: | flowlayout
Which of the following layout classes is in java.awt package? | all of the others.
Which of the following layout managers arranges components in horizontal rows (left to right in the order they were added to their container), starting new rows if necessary? | flow layout
Which of the following layout managers subdivides its territory into a matrix of rows and columns? | grid layout
With respect to the Java socket. (1) A socket contains two binary streams for sending and receiving data. (2) A socket contains two text streams for sending and receiving data. (3) Developers must implement background operations for sending and receiving data. | true, false, false
In a client-server application model, which sides will initiate a connection? | client
With respect to networking and the client-server model. (1) A server runs on a specific computer and has a socket that is bound to a specific port number. The server just waits, listening to the socket for a client to make a connection request. (2) To connect to the server, the client must know the hostname or IP of the machine on which the server is running and the port number on which the server is listening | true, true
In Windows systems, the …… program helps creating the Stub of a RMI server and the …… program will work as a RMI container (RMI registry). | rmic.exe, rmiregistry.exe
Two streams are packed in a socket are ......... | inputstream and outputstream
To implement RMI, classes need to be implemented: (1) Remote interface, (2) Server object, (3) Server program, (4) Client program, (5) Stub object, (6) Transport Object, (7) Remote reference Object | 1, 2, 3, 4, 5
Which of the following statement is correct about object serialization? | transient fields are not serialized
What is the role of RMI registry? | the rmi registry is a program that associates names with rmi services
Select correct statement. In RMI implementations, | the remote class must implement the remote inteface
In Java Network programming using sockets, five steps are usually used: | 1, 2, 3, 4, 5
In a client-server application model, which side will wait for a connection? | server
Suppose you are building a client – server based application using TCP socket technique. Assume at the same time, 5 clients are connecting to the server, and then the server needs to send data to the client number 2. How can the server make sure that it sends the data exactly to the 2nd client, rather than mistakenly to other clients? | the server creates a separate inputstream and outputstream
Which of the following statements is correct? | basically, rmi technology uses traditional sockets but socket classes are created invisibly to developers.
Which of the following protocols is a reliable protocol? | tcp
Two streams in a Java socket are …. | binary streams
A(An) ...…. is one endpoint of a two-way communication link between two programs running on the network. | socket
In RMI Architecture, which of the following components is reponsible for storing a mapping between a specific name and a remote object? | rmi registry
You are building an rmi application. Which of the following interfaces you must extend for your remote interface? | java.rmi.remote
Which of the following options is a valid method that is used to bind a name to an object in RMI model? | naming.rebind(name, object)
With respect to the Java RMI, a server and a client program ……. | can run in two separate virtual machines
Select correct statement. In RMI implementations, | the remote class must implement the remote inteface.
In a client-server application model, which side will initialize a connection? | client
Consider the following url address: | http is protocol, 192.168.2.2:12 is socket.
You are trying to look up obj1 object on the server 192.168.12.1 using RMI technology with default port | naming.lookup("rmi://192.168.12.1/obj
Select a correct statement about TCP and UDP protocol: | tcp (transmission control protocol) is a connection-based protocol that provides a reliable flow of data between two computers.
A/An …… is bound to a port number so that the TCP layer can identify the application having network comunication | socket
The ... object contains not just an SQL statement, but an SQL statement that has been precompiled. | preparedstatement
With respect to JDBC, (1) In the two-tier model, a Java application talks directly to the data source. (2) In the three-tier model, a "middle tier" of services is let between a Java program and the data source. (3) The JDBC API supports two-tier processing model for database access only. | true, true, false
The correct order in which database -accessing objects should be created: | connection – statement- resultset – resultsetmetadata
With respect to the java.sql.Statement interface, | executequery(…), executeupdate(…)
The Java program can | not directly access data in a database file that is managed by a database management system.
The first in the most common objects are used in a database Java program: (1) java.sql.Connection (2) java.sql.Statement (3) java.sql.ResultSet (4) java.sql.ResultSetMetaData | (1) java.sql.connection
Which of the following statements is correct regarding Type 4 JDBC driver (Native Protocol)? | it helps the java applications communicate directly with the database using java sockets.
Suppose that the current position of a ResultSet, named rs, is at the last record, the statement rs.next() will return | false
The JDBC API supports processing models for database access | two-tier model
The _____ object contains not just an SQL statement, but an SQL statement that has been precompiled. | preparedstatement
If you want execute a SQL statement many times, the ____ object should be used. | preparedstatement
You are required to build an application that can connect to database to display data to end users. The requirement for the database connectivity is that it must provide a performance as fast as possible. Suppose that all types of drivers are available. Which type should you choose to satisfy the requirement? | type 2
One of the benefits of Type 1 driver (JDBC – ODBC Bridge) is that it can provide connection to a database when Java driver is not available for that database. Which of the following options is another advantage of the Type 1 driver? | none of the others
Suppose that you will insert a lot of rows into a database table row-by-row. Which of the following interfaces should be used? | preparedstatement
In a JDBC application, suppose that the Connection, named con, was created. Study the following code: | the above code will throw an exception.
In JDBC model, which driver types provide access to database through native code libraries C/C++? | type 2-driver
You are required to build an application that connects to database to store and retrieve data. Your application must be independent with the underlying database. Which driver types should you use? | type 3-driver
You are going to execute an insert statement to add some data into the database. Which of the following methods should you use? | executeupdate()
In JDBC, which of the following class/interface should be used to call a store procedure? | callablestatement
The …. method of the …… class helps loading a JDBC driver. | forname(…), java.lang.class
The next() method of the java.sql.ResultSet class return | a boolean value
When you want to delete some rows in a table of a database, the …… method of the java.sql.Statement interface must be used. | executeupdate()
In JDBC API, which of the following statements can be used to call a stored procedure? | callablestatement
Which of the following is NOT a benefit of using JDBC? | jdbc programs are tightly integrated with the server operating system.
In which layer of the JDBC architecture does the JDBC-ODBC bridge reside? | it resides in the jdbc layer.
What is the range of data type short in Java? | -32768 to 32767
What is the range of data type byte in Java? | -128 to 127.
Which of the following are legal lines of Java code?1. int w = (int)888.8;2. byte x = (byte)100L;3. long y = (byte)100;4. byte z = (byte)100L; | all statements are correct.
An expression involving byte, int, and literal numbers is promoted to which of these? | int
Which of these literals can be contained in a data type float variable? | 3.4e-038
Which data type value is returned by all transcendental math functions? | double
What is the numerical range of a char in Java? | 0 to 65535
Which of these coding types is used for data type characters in Java? | unicode
Which of these values can a boolean variable contain? | true & false
Which of these occupy first 0 to 127 in Unicode character set used for characters in Java? | ascii and iso-latin1
Which one is a valid declaration of a boolean? | boolean b3 = false;
Which of these is data type long literal? | 0x99fffl
Which of these is returned by operators &, ? | character
Literals in java must be preceded by which of these? | l and i
Literal can be of which of these data types? | all of the mentioned
Which of these can not be used for a variable name in Java? | keyword
Which of these is incorrect string literal? | “hello
Which of these operators is used to allocate memory to array variable in Java? | c) new
Which of these is an incorrect array declaration? | int arr[] = int [5] new
What will this code print? int arr[] = new int [5]; System.out.print(arr); | garbage value
Which of these is an incorrect Statement? | it is necessary to use new operator to initialize an array.
Which of these is necessary to specify at time of array initialization? | row
Which of the following can be operands of arithmetic operators? | both numeric & characters
Modulus operator, %, can be applied to which of these? | both integers and floating – point numbers.
With x = 0, which of the following are legal lines of Java code for changing the value of x to 1? | 2. x = x + 1;3. x += 1;
Decrement operator, –, decreases value of variable by what number? | a) 1
Which of these statements are incorrect? | none
Which of these is not a bitwise operator? | a) &
On applying Left shift operator, <<, on an integer bits are lost one they are shifted past which position bit? | b) 32
Which of these statements are incorrect | the right shift operator automatically fills the higher order bits with 0.
What is the output of relational operators? | boolean
Which of these is returned by greater than, <, and equal to, ==, operator? | c) boolean
Which of these statement is correct? | true and false are non numeric values
Which of these have highest precedence? | a) ()
What should be expression1 evaluate to in using ternary operator as in this line?expression1 ? expression2 : expression3 | boolean
What is the value stored in x in following lines of code? | d) 8
What is the order of precedence (highest to lowest) of following operators? | & -> ^-> ?
Which of these statements are incorrect? | division operator, /, has higher precedence than multiplication operator.
Which of these lines of code will give better performance? | both 1 & 2 will give equal performance.
Which of these selection statements test only for equality? | switch
Which of these are selection statements in Java? | if()
Which of the following loops will execute the body of loop even when condition controlling the loop is initially false? | do-while
Which of these jump statements can skip processing remainder of code in its body for a particular iteration? | continue
Which of these statement is correct? | two case constants in the same switch can have identical values.
What is the stored in the object obj in following lines of code?box obj; | null
Which of these keywords is used to make a class? | class
Which of the following is a valid declaration of an object of class Box | box obj = new box();
Which of these operators is used to allocate memory for an object? | new
Which of these statement is incorrect? | every class must contain a main() method.
Which of the following statements is correct? | public method is accessible to all other classes in the hierarchy
What is the return type of a method that does not returns any value | void
What is the process of defining more than one method in a class differentiated by method signature | function overloading
Which of the following is a method having same name as that of it’s class? | constructor
Which method can be defined only once in a program? | main method
Which of these statement is incorrect? | all object of a class are allotted memory for the methods defined in the class.
What is the return type of Constructors | none of the mentioned
Which keyword is used by method to refer to the object that invoked it? | this
Which of the following is a method having same name as that of its class? | constructor
Which operator is used by Java run time implementations to free the memory of an object when it is no longer needed? | none of the mentioned
Which function is used to perform some action when the object is to be destroyed? | finalize()
What is process of defining two or more methods within same class that have same name but different parameters declaration? | method overloading
Which of these can be overloaded? | all of the mentioned
Which of these is correct about passing an argument by call-by-value process? | copy of argument is made into the formal parameter of the subroutine.
What is the process of defining a method in terms of itself, that is a method that calls itself? | recursion
Which of these access specifiers must be used for main() method? | public
Which of these is used to access member of class before object of that class is created? | static
Which of these is used as default for a member of a class if no access specifier is used for it? | private
What is the process by which we can control what parts of a program can access the members of a class? | encapsulation
Which of these access specifier must be used for class so that it can be inherited by another sub class? | public
Arrays in Java are implemented as? | object
Which of these keywords is used to prevent content of a variable from being modified? | final
Which of these cannot be declared static? | object
Which of the following statements are incorrect? | when object of class is declared, each object contains its own copy of static variables.
Which of these methods must be made static? | main()
String in Java is a? | class
Which of these method of String class is used to obtain character at specified index? | charat()
Which of these keywords is used to refer to member of base class from a sub class? | super
Which of these method of String class can be used to test to strings for equality? | equals()
Which of these keyword must be used to inherit a class? | extends
A class member declared protected becomes member of subclass of which type? | private member
Which of these is correct way of inheriting class A by class B? | class b extends a {}
Which of these is correct way of calling a constructor having no parameters, of superclass A by subclass B? | super();
Which of these is supported by method overriding in Java? | polymorphism
Which of these class is superclass of every class in Java? | object class
Which of these method of Object class can clone an object? | object clone()
Which of these method of Object class is used to obtain class of an object at run time? | class getclass()
Which of these keywords can be used to prevent inheritance of a class? | final
Which of these keywords cannot be used for a class which has been declared final? | abstract
Which of these class relies upon its subclasses for complete implementation of its methods? | abstract class
Which of these class is superclass of String and StringBuffer class? | java.lang
Which of these operators can be used to concatenate two or more String objects? | +
Which of these method of class String is used to obtain length of String object? | length()
Which of these method of class String is used to extract a single character from a String object? | string()
Which of these is an oncorrect statement? | stringbuffer class is used to store string in a buffer for later use.
Which of these method of class String is used to extract more than one character at a time a String object? | getchars()
Which of these methods is an alternative to getChars() that stores the characters in an array of bytes? | getbytes()
Which of these method of class String is used to extract a single character from a String object? | charat()
Which of these methods can be used to convert all characters in a String into a character array? | all of the mentioned
Which of these method of class String is used to compare two String objects for their equality? | equals()
Which of these methods is used to compare a specific region inside a string with another specific region in another string? | regionmatches()
Which of these method of class String is used to check weather a given object starts with a particular string literal? | startswith()
What is the value returned by unction compareTo() if the invoking string is less than the string compared? | value less than zero
Which of these data type value is returned by equals() method of String class? | boolean
Which of these method of class String is used to extract a substring from a String object? | substring()
Which of these method of class String is used to remove leading and trailing whitespaces? | trim()
What is the value returned by function compareTo() if the invoking string is less than the string compared? | value less than zero
Which of these class is used to create an object whose character sequence is mutable? | stringbuffer()
Which of these method of class StringBuffer is used to concatenate the string representation to the end of invoking string? | append()
Which of these method of class StringBuffer is used to find the length of current character sequence? | length()
Which of these method of class StringBuffer is used to extract a substring from a String object? | substring()
Which of these method of class StringBuffer is used to reverse sequence of characters? | reverse()
Which of these method of class StringBuffer is used to get the length of sequence of characters? | length()
Which of the following are incorrect form of StringBuffer class constructor? | stringbuffer(int size , string str)
Which of these keywords is used to define packages in Java? | package
Which of these is a mechanism for naming and visibility control of a class and its content? | packages
Which of this access specifies can be used for a class so that its members can be accessed by a different class in the same package? | all of the mentioned
Which of these access specifiers can be used for a class so that it’s members can be accessed by a different class in the different package? | public
Which of the following is correct way of importing an entire package ‘pkg’? | import pkg.*
Which of the following is incorrect statement about packages? | a package can be renamed without renaming the directory in which the classes are stored.
Which of the following package stores all the standard java classes? | java
Which of these keywords is used to define interfaces in Java? | interface
Which of these can be used to fully abstract a class from its implementation? | interfaces
Which of these access specifiers can be used for an interface? | public
Which of these keywords is used by a class to use an interface defined previously? | implements
Which of the following is correct way of implementing an interface salary by class manager? | class manager implements salary {}
Which of these classes is not included in java.lang? | array
Which of these is a process of converting a simple data type into a class? | type wrapping
Which of these is a super class of wrappers Double & Integer? | number
Which of these is wrapper for simple data type float? | float
Which of the following is method of wrapper Float for converting the value of an object into byte? | byte bytevalue()
Which of these methods is used to check for infinitely large and small values? | isinfinite()
Which of the following package stores all the simple data types in java? | lang
Which of these is a wrapper for data type int? | integer
Which of the following methods is a method of wrapper Integer for obtaining hash code for the invoking object? | int hashcode()
Which of these is a super class of wrappers Long, Character & Integer? | number
Which of these is wrapper for simple data type char? | character
Which of the following is method of wrapper Integer for converting the value of an object into byte? | byte bytevalue()
Which of these methods is used to obtain value of invoking object as a long? | long longvalue()
Which of these class have only one field ‘TYPE’? | void
Which of the following method of Process class can terminate a process? | void destroy()
Standard output variable ‘out’ is defined in which class? | system
Which of these class can encapsulate an entire executing program? | process
Which of the following is method of System class is used to find how long a program takes to execute? | currenttimemillis()
Which of these class holds a collection of static methods and variables? | system
Which of these class is superclass of all other classes? | object
Which of these method of Object class can generate duplicate copy of the object on which it is called? | clone()
What is the value of double constant ‘E’ defined in Math class? | approximately 2.72
Which of these method is a rounding function of Math class? | all of the mentioned
Which of these class contains only floating point functions? | math
Which of these class encapsulate the run time state of an object or an interface? | class
Which of these packages contain classes and interfaces used for input & output operations of a program? | java.io
Which of these class is not a member class of java.io package? | string
Which of these interface is not a member of java.io package? | objectfilter
Which of these class is not related to input and output stream in terms of functioning? | file
Which of these is specified by a File object? | directory in disk
Which of these is method for testing whether the specified element is a file or a directory? | isfile()
Which of these classes is used for input and output operation when working with bytes? | inputstream
Which of these class is used to read and write bytes in a file? | fileinputstream
Which of these method of InputStream is used to read integer representation of next available byte input? | read()
Which of these data type is returned by every method of OutputStream? | none of the mentioned
Which of these is a method to clear all the data present in output buffers? | flush()
Which of these is method is used for writing bytes to an outputstream? | print()
Which of these stream contains the classes which can work on character stream? | character stream
Which of these class is used to read characters in a file? | filereader
Which of these method of FileReader class is used to read characters from a file? | read()
Which of these class can be used to implement input stream that uses a character array as the source? | chararrayreader
Which of these classes can return more than one character to be returned to input stream? | pushbachreader
Which of these is a process of writing the state of an object to a byte stream? | serialization
Which of these process occur automatically by java run time system? | serialization
Which of these is an interface for control over serialization and deserialization? | externalization
Which of these interface extends DataOutput interface? | objectoutput
Which of these is a method of ObjectOutput interface used to finalize the output state so that any buffers are cleared? | flush()
Which of these is method of ObjectOutput interface used to write the object to input or output stream as required? | writeobject()
Which of these is a process of extracting/removing the state of an object from a stream? | deserialization
Which of these process occur automatically by java run time system? | all of the mentioned
Which of these interface extends DataInput interface? | objectinput
Which of these is a method of ObjectInput interface used to deserialize an object from a stream? | object readobject()
Which of these package contains classes and interfaces for networking? | java.net
Which of these is a protocol for breaking and sending packets to an address across a network? | tcip/ip
How many ports of TCP/IP are reserved for specific protocols? | 1024
How many bits are in a single IP address? | 32
Which of these is a full form of DNS? | domian name service
Which of these class is used to encapsulate IP address and DNS? | inetaddress
What does URL stands for? | uniform resource locator
Which of these exception is thrown by URL class’s constructors? | malformedurlexception
Which of these methods is used to know host of an URL? | gethost()
Which of these methods is used to know the full URL of an URL object? | toexternalform()
Which of these class is used to access actual bits or content information of a URL? | all of the mentioned
Which of these is wrapper around everything associated with a reply from an http server? | http
Which of these tranfer protocol must be used so that URL can be accessed by URLConnection class object? | http
Which of these methods is used to know when was the URL last modified? | getlastmodified()
Which of these methods is used to know the type of content used in the URL? | getcontenttype()
Which of these data member of HttpResponse class is used to store the response from a http server? | statuscode
Which of these standard collection classes implements a dynamic array? | arraylist
Which of these class can generate an array which can increase and decrease in size automatically? | a) arraylist()
Which of these method can be used to increase the capacity of ArrayList object manually? | d) ensurecapacity()
Which of these method of ArrayList class is used to obtain present size of an object? | size()
Which of these methods can be used to obtain a static array from an ArrayList object? | a) array()
Which of these method is used to reduce the capacity of an ArrayList object? | d) trimtosize()
Which of these classes implements Set interface? | hashset
Which of these method is used to add an element to the start of a LinkedList object? | addfirst()
Which of these method of HashSet class is used to add elements to its object? | add()
Which of these methods can be used to delete the last element in a LinkedList object? | removelast()
Which of these method is used to change an element in a LinkedList Object? | redo()
Which of these object stores association between keys and values? | map
Which of these classes provide implementation of map interface? | hashmap
Which of these method is used to remove all keys/values pair from the invoking map? | remove()
Which of these method Map class is used to obtain an element in the map having specified key? | search()
Which of these methods can be used to obtain set of all keys in a map? | keyset()
Which of these method is used add an element and corresponding key to a map? | put()
Which of these standard collection classes implements all the standard functions on list data structure? | array
Which of these method is used to make all elements of an equal to specified value? | fill()
Which of these method of Array class is used sort an array or its subset? | sort()
Which of these methods can be used to search an element in a list? | binaryserach()
Which of these class object can be used to form a dynamic array? | arraylist & map
Which of these are legacy classes? | all of the mentioned
Which of these is the interface of legacy? | enumeration
What is the name of data member of class Vector which is used to store number of elements in the vector? | elementcount
Which of these methods is used to add elements in vector at specific location? | addelement()
Which of these class object uses key to store value? | all if the mentioned
Which of these method is used to insert value and its key? | put()
Which of these is the interface of legacy is implemented by Hashtable and Dictionary classes? | map
Which of these is a class which uses String as a key to store the value in object? | properties
Which of these methods is used to retrieve the elements in properties object at specific location? | getproperty()
Which of these class object has architecture similar to that of array? | bitset
Which of these method is used to make a bit zero specified by the index? | clear()
Which of these method is used to calculate number of bits required to hold the BitSet object? | length()
Which of these is a method of class Date which is used to search weather object contains a date before the specified date? | before()
Which of these methods is used to retrieve elements in BitSet object at specific location? | get()
Which of these is the method which is executed first before execution of any other thing takes place in a program? | static method
What is the process of defining more than one method in a class differentiated by parameters? | function overloading
Which of these can be used to diffrentiate two or more methods having same name? | all of the mentioned
Which of these data tupe can be used for a method having a return statement in it? | all of the mentioned
When does Exceptions in Java arises in code sequence? | run time
Which of these keywords is not a part of exception handling? | thrown
Which of these keywords must be used to monitor for exceptions? | try
Which of these keywords must be used to handle the exception thrown by try block in some rational manner? | catch
Which of these keywords is used to manually throw an exception? | throw
Which of these is a super class of all exceptional type classes? | throwable
Which of these class is related to all the exceptions that can be caught by using catch? | exception
Which of these class is related to all the exceptions that cannot be caught? | error
Which of these handles the exception when no catch is used? | default handler
Which of these keywords is used to generate an exception explicitly? | throw
Which of these class is related to all the exceptions that are explicitly thrown? | throwable
Which of these operator is used to generate an instance of an exception than can be thrown by using throw? | new
Which of these keywords is used to by the calling function to guard against the exception that is thrown by called function? | throws
What does AWT stands for? | abstract window toolkit
Which of these is used to perform all input & output operations in Java? | streams
Which of these is a type of stream in Java? | byte stream
Which of these classes are used by Byte streams for input and output operation? | inputstream
Which of these classes are used by character streams for input and output operations? | writer
Which Which of these method of these class is used to read from byte array? | bytearrayinputstream.
Which exception is thrown by read() method? | ioexception
Which of these is used to read a string from the input stream? | readline()
Which of these class is used to read characters and strings in Java from console? | bufferedreader
Which of these class is implemented by FilterInputStream class? | inputstream
Which of these class is used to read from a file? | fileinputstream
Which of these class contains the methods print() & println()? | printstream
Which of these methods can be used to writing console output? | all of the mentioned
Which of these classes are used by character streams output operations? | writer
Which of these class contains the methods used to write in a file? | fileinputstream
Which of these exception is thrown in cases when the file specified for writing it not found? | filenotfoundexception
Which of these methods are used to read in from file? | read()
Which of these values is returned by read() method is end of file (EOF) is encountered? | -1
Which of these exception is thrown by close() and read() methods? | ioexception
Which of these methods is used to write() into a file? | write()
Which of these functions is called to display the output of an applet? | print()
Which of these methods can be used to output a sting in an applet? | drawstring()
Which of these methods is a part of Abstract Window Toolkit (AWT) ? | print()
Which of these modifiers can be used for a variable so that it can be accessed from any thread or parts of a program? | volatile
Which of these operators can be used to get run time information about an object? | instanceof
Which of these package is used for graphical user interface? | java.awt
Which of these package is used for analyzing code during run-time? | java.lang.reflect
Which of these package is used for handling security related issues in a program? | java.security
Which of these class allows us to get real time data about private and protected member of a class? | reflectpermission
Which of these package is used for invoking a method remotely? | java.rmi
Which of these package is used for all the text related modifications? | java.text
What is Remote method invocation (RMI)? | rmi allows us to invoke a method of java object that executes on another machine.
Which of these package is used for remote method invocation? | java.rmi
Which of these methods are member of Remote class? | none of the mentioned
Which of these Exceptions is thrown by remote method? | remoteexception
Which of these class is used for creating a client for a server-client operations? | addclient.java
Which of these package is used for text formatting in Java programming language? | java.text
Which of this class can be used to format dates and times? | dateformat
Which of these method returns an instance of DateFormat that can format time information? | gettimeinstance()
Which of these class allows us to define our own formatting pattern for dates and time? | simpledateformat
Which of these formatting strings of SimpleDateFormat class is used to print AM or PM in time? | a
Which of these formatting strings of SimpleDateFormat class is used to print week of the year? | w
Which of these method can be used to make the main thread to be executed last among all the threads? | sleep()
Which of these method is used to find out that a thread is still running or not? | isalive()
What is the default value of priority variable MIN_PRIORITY AND MAX_PRIORITY? | 1 & 10
Which of these method waits for the thread to treminate? | join()
Which of these method is used to explicitly set the priority of a thread? | setpriority()
What is synchronization in reference to a thread? | it’s a process of handling situations when two or more threads need access to a shared resource.
Which of these method is used to implement Runnable interface? | run()
Which of these interface is implemented by Thread class? | runnable
Which of these method is used to begin the execution of a thread? | start()
Which of these class is used to make a thread? | thread
Which of these method of Thread class is used to find out the priority given to a thread? | getpriority()
Which of these method of Thread class is used to Suspend a thread for a period of time? | sleep()
Which function of pre defined class Thread is used to check weather current thread being checked is still running? | isalive()
What is multithreaded programming? | it’s a process in which two or more parts of same process run simultaneously.
Which of these are types of multitasking? | process and thread based
Which of these packages contain all the Java’s built in exceptions? | java.lang
Thread priority in Java is? | integer
What will happen if two thread of same priority are called to be processed simultaneously? | it is dependent on the operating system
Which of these clause will be executed even if no exceptions are found? | finally
A single try block must be followed by which of these? | finally & catch
Which of these exceptions handles the divide by zero error? | arithmeticexception
Which of these exceptions will occur if we try to access the index of an array beyond its length? | arrayindexoutofboundsexception
Which of these keywords are used to implement synchronization ? | synchronized
Which of these method is used to avoid polling in Java? | all of the mentioned
Which of these method is used to tell the calling thread to give up monitor and go to sleep until some other thread enters the same monitor? | wait()
Which of these method wakes up all the threads? | notifyall()
What is synchronization in reference to a thread? | its a process of handling situations when two or more threads need access to a shared resource.
Which of these packages contains all the classes and methods required for even handling in Java? | java.awt.event
What is an event in delegation event model used by Java programming language? | an event is an object that describes a state change in a source.
Which of these methods are used to register a keyboard event listener? | addkeylistener()
Which of these methods are used to register a mouse motion listener? | addmousemotionlistner()
What is a listener in context to event handling? | a listener is a object that is notified when an event occurs.
Event class is defined in which of these libraries? | java.util
Which of these methods can be used to determine the type of event? | getid()
Which of these class is super class of all the events? | eventobject
Which of these events will be notified if scroll bar is manipulated? | adjustmentevent
Which of these events will be generated if we close an applet’s window? | windowevent
Which of these events is generated when a button is pressed? | actionevent
Which of these methods can be used to obtain the command name for invoking ActionEvent object? | getactioncommand()
Which of these are integer constants defined in ActionEvent class? | all of the mentioned
Which of these methods can be used to know which key is pressed? | getmodifier()
Which of these events is generated by scroll bar? | adjustmentevent
Which of these methods can be used to determine the type of adjustment event? | getadjustmenttype()
Which of these methods can be used to know the degree of adjustment made by the user? | getvalue()
Which of these constant value will change when the button at the end of scroll bar was clicked to increase its value? | unit_increment
Which of these events is generated when the size os an event is changed? | componentevent
Which of these events is generated when the component is added or removed? | containerevent
Which of these methods can be used to obtain the reference to the container that generated a ContainerEvent? | getcontainerevent()
Which of these methods can be used to get reference to a component that was removed from a container? | getchild()
Which of these are integer constants of ComponentEvent class? | all of the mentioned
Which of these events is generated when computer gains or losses input focus? | focusevent
FocusEvent is subclass of which of these classes? | componentevent
Which of these methods can be used to know the type of focus change? | istemporary()
Which of these is superclass of ContainerEvent class? | componentevent
Which of these events is generated when the a window is closed? | windowevent
Which of these methods can be used to obtain the coordinates of a mouse? | getpoint()
Which of these methods can be used to change location of an event? | translatepoint()
Which of these are integer constants of TextEvent class? | text_format_changed
Which of these methods is used to obtain the object that generated a WindowEvent? | getwindow()
MouseEvent is subclass of which of these classes? | inputevent
Which of these methods is used to get x coordinate of the mouse? | getxcoordinate()
Which of these are constants defined in WindowEvent class? | all of the mentioned
Which of these is superclass of WindowEvent class? | componentevent
Which of these is superclass of WindowEvent class? | inputevent
Which of these packages contains all the event handling interfaces? | java.awt.event
Which of these interfaces handles the event when a component is added to a container? | containerlistener
Which of these interfaces define a method actionPerformed()? | actionlistener
Which of these interfaces define four methods? | componentlistener
Which of these interfaces define a method itemStateChanged()? | itemlistener
Which of these methods will respond when you click any button by mouse? | all of the mentioned
Which of these methods will be invoked if a character is entered? | keytyped()
Which of these methods is defined in MouseMotionAdapter class? | mousedragged()
Which of these is superclass of all Adapter classes? | applet
You can determine  all the keys in a Map in which of the following ways? | by getting a set object from the map and iterating  through it.
What keyword  is used to prevent an object from being serialized? | transient
An abstract class can contain  methods  with declared bodies. | true
Select the order of access modifiers from least restrictive to most restrictive | public, protected, default,  private
Which access modifier allows you to access method  calls in libraries not created in Java? | native
Which of the following statements  are true? (Select all that apply.) | a final object cannot  be reassigned a new address in memory.
The keyword  extends refers to what type of relationship? | “is a”
Which of the following keywords  is used to invoke a method  in the parent  class? | super
public static  void main(String []  a) { Funcs   f = new Funcs(); System.out.println("" + f.add(1, 2)); | the code does not compile.
public static  void main(String []  a) { int [] b  = [1,2,3,4,5,6,7,8,9,0]; System.out.println("a[2]=" + a[2]); | the code does not compile.
What is the value of x after the following operation is performed? x  = 23  %   4; | 3
Given the following code, what keyword  must be used at line 4 in order to stop execution of the for loop? boolean b  = true; for (;;) { if (b)  { | break
What method  call is used to tell a thread  that it has the opportunity to run? | notify()
Given the following code, which of the results that follow would you expect?   package mail; interface Box { protected  void open(); void close(); public  void empty(); | the code will not compile because of line 4.
Assertions are used to enforce all but which of the following? | exceptions
The developer can force garbage collection by calling System.gc(). | false
Select the valid primitive data types. (Select all that apply.) | boolean char float
How many bits does a float contain? | 32
What is the value of x after the following line is executed? x  = 32  *  (31   - 10  *  3); | 32
A StringBuffer is slower than a StringBuilder, but a StringBuffer is threadsafe. | true
Select the list of primitives ordered  in smallest to largest bit size representation. | char, int, float, long
Which class provides locale-sensitive text formatting for date and time information? | java.text.dateformat
The following line of code is valid. int x  = 9; byte b  = x; | false
Which of the following code snippets compile? | integer i =  7; b.	integer i =  new integer(5); int j =  i; c.	byte b  =  7;
What will be the output of the following code? public class  StringTest { public static  void main(String []  a) { String s1  = "test string"; String s2  = "test string"; if (s1 == s2)  { System.out.println("same"); }  else  { System.out.println("different"); | “same” will be printed  out to the console.
Java arrays always start at index 1. | false
Which of the following statements  accurately  describes how variables are passed to methods? | arguments  that are primitive type are passed by value.
How  do you change the value that  is encapsulated by a wrapper class after you have instan- tiated it? | none of the above.
Suppose you are writing a class that provides custom deserialization. The class implements java.io.Serializable (and not java.io.Externalizable). What method  should imple- ment the custom deserialization, and what is its access mode? | private  readobject
A signed data type has an equal number  of non-zero  positive and negative values available. | false
Choose the valid identifiers from those listed here. (Choose all that apply.) | bigollongstringwithmeaninglessname b.	$int c.	bytes d.	$1 e.	finalist
Which of the following signatures are valid for the main() method entry point of an application? (Choose all that apply.) | public static  void main(string arg[]) d.	public static  void main(string[] args)
If all three top-level elements occur in a source file, they must appear  in which order? | package declaration, imports,  class/interface/enum definitions.
Consider  the following line of code: int[] x  = new int[25]; After execution,  which statements  are true? (Choose all that apply.) | x[24] is 0 e.	x.length is 25
Consider  the following application: class Q7 { public static  void main(String args[])  { double d  = 12.3; Decrementer dec  = new Decrementer(); dec.decrement(d); System.out.println(d); } } class Decrementer  { public  void decrement(double decMe)  { decMe = decMe - 1.0; | 12.3
How can you force garbage collection of an object? | garbage  collection cannot  be forced.
What is the range of values that can be assigned to a variable of type short? | -215  through 215   - 1
What is the range of values that can be assigned to a variable of type byte? | -27  through 27  - 1
Suppose a source file contains a large number  of import statements. How do the imports  affect the time required  to compile the source file? | compilation takes slightly more time
Suppose a source file contains  a large number  of import statements  and one class definition. How do the imports  affect the time required  to load the class? | class loading takes no additional time.
Which of the following are legal import statements? | import  java.util.vector; c.	import  static java.util.vector.*;
Which of the following may be statically imported? (Choose all that apply.) | static method  names c.	static field names
What happens  when you try to compile and run the following code? public class Q15 { static  String s; public static  void main(String[]  args)  { System.out.println(“>>” + s + “<<”); | the code compiles, and prints out >>null<<
Which of the following are legal? (Choose all that apply.) | int c  =  0xabcd; d.	int d  =  0xabcd;
Which of the following are legal? (Choose all that apply.) | double d  =  1.2d; b.	double d  =  1.2d;
Which of the following are legal? | char c  =  ‘\u1234’;
Consider  the following code: StringBuffer  sbuf = new StringBuffer(); sbuf = null System.gc(); | after line 2 executes, the stringbuffer object is eligible for garbage collection.
Which of the following are true? (Choose all that apply.) | primitives are passed by value. d.	references are passed by value.
After execution  of the following code fragment,  what are the values of the variables x, a, and b? int x, a  = 6, b  = 7; x  = a++  + b++; | x = 13, a = 7, b = 8
Which of the following expressions  are legal? (Choose all that apply.) | int x  =  6; if (!(x >  3))  {} c.	int x  =  6; x  =  ~x;
Which of the following expressions  results in a positive value in x? | int x  =  –1; x  =  x  >>> 5;
Which of the following expressions  are legal? (Choose all that apply.) | string x  =  "hello"; int y  =  9; x  += y;  c.	string x  =  "hello"; int y  =  9; x  =  x  +  y;
What results from running  the following code? public class Xor  { public static  void main(String args[])  { byte b  = 10; // 00001010   binary byte c  = 15; // 00001111   binary b  = (byte)(b ^  c); System.out.println("b contains " + b); | the output: b  contains  5
What results from attempting to compile and run the following code? public class  Conditional { public static  void main(String args[])  { int x  = 4; System.out.println("value is  " + ((x > 4) ?  99.99 : 9)); | the output: value  is 9.0
What does the following code do? Integer i = null; if (i !=  null   &      i.intValue() == 5) System.out.println(“Value is  5”); | throws  an exception.
Is it possible to define a class called Thing  so that the following method  can return  true under certain circumstances? boolean weird(Thing s)  { Integer x  = new Integer(5); return s.equals(x); | yes
Suppose ob1  and ob2  are references to instances of java.lang.Object. If (ob1 == ob2) is false, can ob1.equals(ob2) ever be true? | no
Which statement is true about  the following method? int selfXor(int i)  { return i ^  i; | it always returns  0.
Which of the following operations might throw  an ArithmeticException? | /
What is the return  type of the instanceof operator? | a boolean
Which of the following may appear  on the left-hand  side of an instance of operator? | a. a reference
Which of the following may appear on the right-hand side of an instance of operator? (Choose all that apply.) | b. a class c. an interface
What is -50  >>  1? | -25
Which of the following declarations are illegal? (Choose all that apply.) | a. default string s; d. abstract  double d; e. abstract  final  double hyperboliccosine();
Which of the following statements  is true? | b. a final class may not have any abstract methods.
What is the minimal modification that will make this code compile correctly? final class Aaa { int xxx; void yyy() {  xxx  = 1; } }  class Bbb extends Aaa { final Aaa  finalref =  new  Aaa(); final  void yyy() { System.out.println("In method  yyy()"); finalref.xxx = 12345; } } | a. on line 1, remove the final modifier.
4.	Which of the following statements  is true? | e. transient variables are not serialized
5.	Which statement is true about  this application? class StaticStuff { static int x  = 10; static {  x  += 5; } public static  void main(String args[]) { System.out.println("x = " + x); } static {x  /= 5; } } | e. the code compiles and execution  produces  the output x = 3.
6.	Which statement is true about  this code? class HasStatic { private static int x  = 100; public static  void main(String args[]) { HasStatic hs1  = new HasStatic(); hs1.x++; HasStatic hs2  = new HasStatic(); hs2.x++; hs1  = new HasStatic(); hs1.x++; HasStatic.x++; System.out.println("x = " + x); } } | e. the program compiles and the output is x = 104.
7.	Given the following code, and making no other changes, which combination of access modifiers (public, protected, or private) can legally be placed before aMethod() on line 3 and be placed before aMethod() on line 8? class SuperDuper { void  aMethod() {  } } class Sub  extends SuperDuper { void  aMethod() {  } } | d. line 3: private; line 8: protected
8.	Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class’s persistent  state? (Choose the shortest  possible answer.) | d. transient
11.	Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides  doSomething(). What  access modes may Subby’s version of the method  have? (Choose all that  apply.) | a. public b. protected
12.	Which of the following statements  are true? | f. none of the above.
13.	Suppose interface Inty defines five methods.  Suppose class Classy declares that it implements Inty but does not provide implementations for any of the five interface methods. Which is/are true? | the class will compile if it is declared abstract. d.	the class may not be instantiated.
14.	Which of the following may be declared final? (Choose all that apply.) | a. classes b. data c. methods
15.	Which of the following may follow the static keyword?  (Choose all that apply.) | b. data c. methods d.	code blocks enclosed in curly brackets
16.	Suppose class A has a method  called doSomething(), with default access. Suppose class B extends A and overrides  doSomething(). Which access modes may apply to B’s version of doSomething()? (Choose all that apply.) | a. public c. protected d. default
17.	True or false: If class Y extends class X, the two classes are in different packages, and class X has a protected  method  called abby(), then any instance of Y may call the abby() method  of any other instance of Y. | b. false
18.	Which of the following statements  are true? | d. a final class may not be extended.
1.	Which of the following statements  is correct? (Choose one.) | both primitives and object references can be both converted  and cast.
5.	float f =  555.5f; 6.	b  =  s; 7.	i =  c; | f.	line  6
4.	In the following code, what are the possible types for variable result? (Choose the most complete true answer.) 1.	byte b  = 11; 2.	short s = 13; 3.	result = b  *  ++s; | int, long, float, double
6.	Which of the following statements  is true? (Choose one.) | object references can be converted  in both method  calls and assignments,  and the rules governing these conversions  are identical.
is a set of java API  for executing SQL statements. | jdbc
drivers that are written partly in the Java programming language and partly in native code. These drivers use a native client library specific to the data source to which they connect. Again, because of the native code, their portability is limited. | type 2
drivers that are pure Java and implement the network protocol for a specific data source. The client connects directly to the data source. | type 4
drivers that use a pure Java client and communicate with a middleware server using a database-independent protocol. The middleware server then communicates the client's requests to the data source. | type 3
drivers that implement the JDBC API as a mapping to another data access API, such as ODBC. Drivers of this type are generally dependent on a native library, which limits their portability. | type 1
26. System.out.println(a.doit(4, 5)); | line 26 prints “a” to system.out.
Which two are true if a NullPointerException is thrown on line 3 of class C? (Choose two.) | the code on line 29 will be executed. e.	the exception will be propagated back to line 27.
dialog prevents user input to other windows in the application unitl the dialog is closed. | modal
An object is used to submit a query to a database | statement
An object is uses to obtain a Connection to a Database | driver manager
A programmer wants to create an interface called B that has A as its parent. Which interface declaration is correct? | public interface b extends a { }
How many locks does an object have? (Choose one.) | 1
Interface ...   helps manage the connection between a Java program and a database. | connection
DBC supports ... 	 and  ...	 models. | two-tier and three-tier
Select incorrect statement about Socket class. (choose 1) | the java.net.socket class contains code that knows how to find and communicate with a server through udp.
SQL keyword  ...	 is followed by the selection criteria that specify the rows to select in a query | where
Statement objects return SQL query results as ... 	 objects | resultsetsuppose a source file contains a large number of import statements and one class definition. how do the imports affect the time required to load the class? (choose one.)  |   Class loading takes no additional time.
Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions. You decide to subclass java.lang.Math and provide the new functionality as a set of static methods. Which one statement is true about this strategy? | the strategy fails because you cannot add static methods to a subclass.
The ... 	 class is the primary class that has the driver information. | driver manager
The ... 	 class is used to implement a pull-down menu that provides a number of items to select from. | menu
The Swing component classes can be found in the package. | javax.swing
What is the range of values that can be assigned to a variable of type byte? | -2^7 through 2^7 - 1
When a negative byte is cast to a long, what are the possible values of the result? | negative
When a negative long is cast to a byte, what are the possible values of the result? | all the above
When comparing java.io.BufferedWriter to java.io.FileWriter, which capability exists as a method in only one of the two? | writing a line separator to the stream
When is x & y an int? | sometimes
When the user attempts to close the frame window,  ...	 event in generated. | window closing
When the user selects a menu item,  ...	 event is generated. | action event
When you compile a program written in the Java programming language, the compiler converts the human-readable source file into platform- independent code that a Java Virtual Machine can understand. What is this platform-independent code called? | bytecode
Whenever a method does not want to handle exceptions using the try block, the ...  	 is used. | throws
Which class and static method can you use to convert an array to a List? | arrays.aslist
Which is four-step approach to help you organize your GUI thinking. | identify needed components. isolate regions of behavior. sketch the gui. choose layout managers.
Which is the four steps are used in working with JDBC? | connect to the database create a statement and execute the query look at the result set close connection
Which Man class properly represents the relationship "Man has the best friend who is a Dog"? | class man { private dog bestfriend; }
Which methods return an enum constant’s name? | name() tostring()
Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class's persistent state? | transient
Which of the following are legal argument types for a switch statement? | byte int char
Which of the following are legal loop definitions? | none of the above.
Which of the following are methods of the java.util.SortedSet interface? | all the above
Which of the following are true? | the jvm runs until there are no non-daemon threads.
Which of the following are true? | an enum may contain public method definitions. an enum may contain private data.
Which of the following are true? | primitives are passed by value.  references are passed by value.
Which of the following are true? | an anonymous inner class may implement at most one interface. an anonymous inner class may extend a parent class other than object.
Which of the following are valid arguments to the DataInputStream constructor? | fileinputstream
Which of the following are valid mode strings for the RandomAccessFile constructor? | all the above
Which of the following calls may be made from a non-static synchronized method? | all the above
Which of the following classes implement java.util.List? | java.util.arraylist java.util.stack
Which of the following classes implements a FIFO Queue? | linkedlist
Which of the following expressions results in a positive value in x? | int x = –1; x = x >>> 5;
Which of the following is not appropriate situations for assertions? | preconditions of a public method
Which of the following may appear on the left-hand side of an instance of operator? | a reference
Which of the following may appear on the right-hand side of an instance of operator? (Choose two.) | class interface
Which of the following may be declared final? (Choose two.) | classes methods
Which of the following may be statically imported? (Choose two.) | static method names static field names
Which of the following operators can perform promotion on their operands? (Choose three.) | + - ~
Which of the following signatures are valid for the main() method entry point of an application? (Choose two.) | public static void main(string[] args) public static void main(string arg[])
A dialog prevents user input to other windows in the application umtl the dialog is closed | modal
public float aMethod(float x. float y) {} | 1
Runtime Exception | 1
What is the output of the following code class Main { static intk- 10; static {k ?- 5;} public static void main(Strmg argsQ){ System outpnntln(k).}static {k 5;}} | 20
Assuming any exception handling has been set up. which of the following will create an instance of the RandomAccessFile class? | randomaccessfile raf-new randomaccessfilefmyfile txr."rw)
How do you prevent shared data from being corrupted in a | access the variables only via synchronized mothods
Compile time error | 1
A thread's run() method includes the following lines 1	try{ 2	sleep(IOO);3.} catch (InterruptedException e) {} | at line 2. the thread will stop running it will resume running some time after 100 milliseconds have elapsed
When a user selects a menu,______is generated | action event
When you compile a program written in the Java programming language, the compiler converts the human-readable source file into platform-independent code that a Java Virtual Machine can understand What is this platform-independent code called? | bytecode
Which of the following operators can perform promotion on their operands? (Select two) | + -
Select INCORRECT statement about FlowLayout | the flow layout manager always honors a component's preferred size d the flow layout manager arranges components in horizontal rows
Which line contains only legal statements? | int x=6 x = ~x
Which Man class properly represents the relationship 'Man has the best friend who is a Dog'? | class man {private bestfnend dog;}
99 100 102 | 1
Select the most correct statement | a thread is in the ready state after it has been created and started
Which of the following statements) is(are) true? 1)An abstract class can not have any final methods 2)A final class may not have any abstract methods | both statement 1 and 2
What is the return type of the instanceof operator? | boolean
Study the statements: 1)	When a JDBC connection is created, it is in auto-commit mode 2)	0nce auto-commit mode is disabled, no SQL statements will be committed until you call the method commit explicitly | both 1 and 2 are true
the code on line 29 will be executed | 1
No such file found. Doing finally.-1 | 1
Which of the following is true about Wrapped classes? | wrapper classes are. boolean. char. byte. short. integer. long. float and double
Which of the followings statements is true? | the gndbaglayout manager is the default manager for jframe
What is the range of values that can be assigned to a variable of type short? | 2 mu 15 through 2 mu 15 -1
Which of the statements below is true"? | when you construct an instance of file, the file will not be created even if the corresponding file does not exist on the local file system
Which of the following may follow the static keyword9 (Select two) | methods and code blocks endosed in curly brackets
Which of the following statements is true | constructors are not inherited
public interface B inheritsFrom A {} | 1
Which of the following statements is true | a for statement can loop infinitely, for example for(;;);
Select INCORRECT statement about deserialize (choose 1) | we use readobjecto method of objectoutputstream dass to deserialize
a#b, a==c | 1
Is it possible to define a dass called Thing so that the following method can return true under certain drcumstances? boolean weirdfThing s) {Integer x = new lnteger(5); return s.equals(x);} | yes
A(n)_____object is uses to obtain a Connection to a Database | dnvermanager
Study the following Java statements:String sl= “Hetlo”;String s2= “Hello";String s3= “Hello";String s4= new Stnng(“Hello");How many strings, specified by the above code, are stored in the memory of the program | 2
What is the difference between a TextArea and a TextField | a textarea can handle multiple lines of text
You have been given a design document for a veterinary registration system for implementation in Java. It states"A pet has an owner, a registration date, and a vacdnation-due date A cat is a pet that has a flag indicating whether it has been neutered, and a textual description of its markings"Given that the Pet class has already been defined, which of the following fields would be appropriate for inclusion in the Cat class as members9 (Select the most appropriate two declarations) | string markings boolean neutered;
Which of the following are valid declarations? Assume java.util.* is imported. | vector<map>   v;set<string> ;map<string, string>  m;\
You can determine  all the keys in a Map in which of the following ways | by getting a set object from the map and iterating  through it.
An abstract class can contain  methods  with declared bodies | true
Which access modifier allows you to access method  calls in libraries not created in Java | native
Which of the following statements  are true? (Select all that apply | a final object cannot  be reassigned a new address in memory
The keyword  extends refers to what type of relationship | g.	“is a”
public class Funcs extends java.lang.Math | the code does not compile.
public  class  Test | the code does not compile.
What is the value of x after the following operation is performed  x  = 23  %   4; | 3
Given the following code, what keyword  must be used at line 4 in order to stop execution of the for loop? | break
interface Box | the code will not compile because of line 4.
Assertions are used to enforce all but which of the following | exceptions
A StringBuffer is slower than a StringBuilder, but a StringBuffer is threadsafe | true
Select the list of primitives ordered  in smallest to largest bit size representation | char, int, float, long
Which of the following code snippets compile | integer i =  7; integer i =  new integer(5); int j =  i;byte b  =  7;
public class  StringTest | “same” will be printed  out to the console.
which of the following statements  accurately  describes how variables are passed to method | arguments  that are primitive type are passed by value.
How  do you change the value that  is encapsulated by a wrapper class after you have instan- tiated it | none of the above
A signed data type has an equal number  of non-zero  positive and negative values available. | fasle
Choose the valid identifiers from those listed here. (Choose all that apply | bigollongstringwithmeaninglessname - $int - bytes - $1 - finalist
Which of the following signatures are valid for the main() method entry point of an application?(Choose all that apply.) | public static  void main(string arg[]) - public static  void main(string[] args)
Consider  the following line of code:int[] x  = new int[25]; After execution,  which statements  are true? (Choose all that apply.) | x[24] is 0 - e.	x.length is 25
class Q6 | 101
class Q7 | 12.3
How can you force garbage collection of an object | garbage  collection cannot  be forced
What is the range of values that can be assigned to a variable of type byte | -27  through 27  - 1
Suppose a source file contains a large number  of import statements. How do the imports  affect the time required  to compile the source file? | compilation takes slightly more time.
Which of the following are legal import statements | import  java.util.vector - import  static java.util.vector.*;
Which of the following may be statically imported? (Choose all that apply.) | static method  names-static field names
public class Q15 | the code compiles, and prints out >>null<<
The code compiles, and prints out >>null<< | int c  =  0xabcd- c.	int c  =  0xabcd
Which of the following are legal? (Choose all that apply.) | double d  =  1.2d; - b.	double d  =  1.2d;
Consider  the following code: StringBuffer  sbuf = new StringBuffer(); sbuf = null; System.gc(); | after line 2 executes, the stringbuffer object is eligible for garbage collection.
Which of the following are true? (Choose all that apply.) | primitives are passed by value. - d.	references are passed by value.
Which of the following expressions  are legal? (Choose all that apply.) | int x  =  6; if (!(x >  3))  {} - c.	int x  =  6; x  =  ~x;
Which of the following expressions  are legal? (Choose all that apply.) | tring x  =  "hello"; int y  =  9; x  += y; - c.	string x  =  "hello"; int y  =  9; x  =  x  +  y;
public class Xor | the output: b  contains  5
public class  Conditional | the output: value  is 9.0
What does the following code do? Integer i = null; if (i !=  null   &      i.intValue() == 5) System.out.println(“Value is  5”); | throws  an exception
Is it possible to define a class called Thing  so that the following method  can return  true under certain circumstances? boolean weird(Thing s)  { Integer x  = new Integer(5); return s.equals(x); } | yes
Which statement is true about  the following method? int selfXor(int i)  { return i ^  i;} | it always returns  0.
Which of the following operations might throw  an ArithmeticException? | none of these
Which of the following operations might throw  an ArithmeticException? | a boolean
Which of the following may appear  on the left-hand  side of an instanceof operator? | a reference
Which of the following may appear on the right-hand side of an instanceof operator? (Choose all that apply.) | a class -c.	an interface
Which of the following declarations are illegal? (Choose all that apply.) | default string s; - d.	abstract  double d; - d.	abstract  double d;
Which of the following statements  is true? | a final class may not have any abstract methods.
final class Aaa | on line 1, remove the final modifier.
Which of the following statements  is true? | transient variables are not serialized.
class StaticStuff | the code compiles and execution  produces  the output x = 3.
class HasStatic | the program compiles and the output is x = 104.
class SuperDuper | line 3: private; line 8: protected
Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class’s persistent  state? (Choose the shortest  possible answer.) | transient
public  class  Bird | compilation of parrot.java fails at line 7 because method  getrefcount() is static in the superclass, and static methods  may not be overridden to be nonstatic.
class  Nightingale extends abcde.Bird | the program will compile and execute. the output will be before: 0    after: 2.
Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides  doSomething(). What  access modes may Subby’s version of the method  have? (Choose all that  apply.) | public - protected
Which of the following statements  are true | f.	none of the above
Suppose interface Inty defines five methods.  Suppose class Classy declares that it implements Inty but does not provide implementations for any of the five interface methods. Which is/are true? | the class will compile if it is declared abstract.- the class may not be instantiated.
Which of the following may be declared final? (Choose all that apply.) | classes - data - methods
Which of the following may follow the static keyword?  (Choose all that apply.) | data - methods - code blocks enclosed in curly brackets
Suppose class A has a method  called doSomething(), with default access. Suppose class B extends A and overrides  doSomething(). Which access modes may apply to B’s version of doSomething()? (Choose all that apply.) | public - protected - default
True or false: If class Y extends class X, the two classes are in different packages, and class X has a protected  method  called abby(), then any instance of Y may call the abby() method  of any other instance of Y. | false
Which of the following statements  are true? | a final class may not be extended.
Which of the following statements  are true | a final class may not be extended.
public class A | -1
Which of the following statements  is correct? (Choose one.) | both primitives and object references can be both converted  and cast.
Which one line in the following code will not compile? | f.	line  6
class  Cruncher | the code will compile and produce  the following output: int version
Which of the following statements  is true? (Choose one | object references can be converted  in both method  calls and assignments,  and the rules governing these conversions  are identical.
Consider  the following code. Which line will not compile? | line 6
Consider  the following code | the code will compile and run.
Cat  sunflower | the code will compile but will throw  an exception  at line 7, because the runtime  class of wawa cannot  be converted  to type swampthing.
Raccoon   rocky; | line 7 will not compile; an explicit cast is required  to convert a washer to a swampthing
Which of the following may legally appear  as the new type (between the parentheses)  in a cast operation | all of the above
Which of the following may legally appear  as the new type (between the parentheses)  in a cast operation? | all of the above
Suppose the declared type of x is a class, and the declared type of y is an interface. When is the assignment  x  =  y; legal? | when the type of x is object
Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment  xarr =  yarr; legal? | sometimes
When is x  &   y an int? (Choose one). | sometimes
What are the legal types for whatsMyType? short s = 10; whatsMyType  = !s; | there are no possible legal types
When a negative long is cast to a byte, what are the possible values of the result | all of the above
Which of the following operators can perform  promotion on their operands? (Choose all that  apply.) | + - ~
What is the difference between the rules for method-call conversion and the rules for assignment conversion? | there is no difference; the rules are the same
for (int i = 0; i < 2;  i++) | i =  0  j =  1 - i =  0  j =  2 - i =  1  j =  0 - i =  1  j =  2
outer: for (int i = 0; i < 2;  i++) | outer: for (int i = 0; i < 2;  i++)
Which of the following are legal loop constructions? (Choose all that apply.) | int j =  0; for (int  k=0, j+k   !=  10;  j++,k++) { system.out.println("j=" +  j +  ", k="  +  k); }
int j = 2; | the output would be the text value is two followed by the text value is three.
What lines are output if the method at line 5 throws an OutOfMemoryError? (Choose all that apply.) | doing  finally part
Which of the following are appropriate situations for assertions | postconditions of a public method - preconditions of a private method - postconditions of a private method
Which of the following is the most appropriate way to handle invalid arguments  in a public method? | throw  java.lang.illegalargumentexception.
Which of the following are legal? (Choose all that apply.) | for (int  i=0, j=1; i<10; i++, j++) - for (int  i=0, j=1;; i++, j++) - for (string s =  “”; s.length()<10; s += ‘!’)
Which of the following are legal loop definitions?  (Choose all that apply.) | none of them are legal.
Which of the following are legal argument types for a switch statement? | byte- int - char
When is it appropriate to pass a cause to an exception’s constructor | when the exception  is being thrown in response to catching of a different exception  type
When does an exception’s stack trace get recorded  in the exception  object? | when the exception  is constructed
When is it appropriate to write code that constructs and throws  an error? | never
public  class  Test1 | public int  amethod(int a,  int  b) {  } - public float  amethod(float a, float b, int c) throws exception {  }- private float amethod(int a,  int  b,  int  c)  {  }
public  class  Test1 | public int  amethod(int a,  int  b) throws exception {...} - public float  amethod(float p, float q) {...}
“A pet has an owner,  a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating whether  it has been neutered,  and a textual  description  of its markings.” | boolean neutered - string  markings
“A pet has an owner,  a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating if it has been neutered,  and a textual  description  of its markings | public class cat   extends pet
public class Base | value   is  5this value is  6
public class  Test extends Base | test t =  new test(1); test t =  new test(1, 2);
public class  Test extends Base | base() {  } - base(int j, int k) {  }
public  class  Outer | a- b - c -e
Which of the following statements  are true? (Choose all that apply.) | given that inner is a nonstatic class declared inside a public class outer and that appro- priate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
Which of the following are legal enums | enum animals {lion,  tiger,  bear; int weight;} - enum animals {lion(450),  tiger(450), bear; int weight;animals() {  } animals(int w)  {weight =  w;}}
Which of the following may override a method  whose signature  is void xyz(float  f)? | void xyz(float  f)  - public void xyz(float  f)
Which of the following are true? (Choose all that apply.) | an enum may contain  public method  definitions. - an enum may contain  private data.
Which of the following are true? (Choose all that apply.) | an enum definition  may contain  the main() method  of an application. - you can call an enum’s tostring() method. - you can call an enum’s wait() method. - you can call an enum’s notify() method.
Suppose x and y are of type TrafficLightState, which is an enum. What is the best way to test whether  x and y refer to the same constant | if (x == y)
Given the following code, which of the following will not compile? enum Spice {  NUTMEG,  CINNAMON,  CORIANDER,   ROSEMARY;  } | string ob = new string(); spice sp = ob;
Which of the following are true | an anonymous inner class may implement  at most one interface. - an anonymous inner class may extend a parent  class other than object
Which methods  return  an enum constant’s  name | name() - tostring()
Suppose class X contains  the following method: void doSomething(int a, float b)  {  …    } Which of the following methods  may appear  in class Y, which extends X? | public  void dosomething(int a, float b) {  …    }
This question  involves IOException, AWTException, and EOFException. They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends IOException. Suppose class X contains  the following method: void  doSomething() throws IOException{ …    } | void  dosomething() {  …    } - void  dosomething()  throws  eofexception {  …    } - void  dosomething() throws ioexception,  eofexception {  …    }
class Greebo   extends java.util.Vector | there will be a compiler error,  because class greebo  does not correctly implement  the runnable interface.
class  HiPri extends Thread | when the application is run, all three threads (hp1, hp2, and hp3) will execute concurrently, taking time-sliced turns in the cpu.
A thread  wants to make a second thread  ineligible for execution.  To do this, the first thread  can call the yield() method  on the second thread. | false
A thread’s run() method  includes the following lines: | at line 2, the thread will stop running. it will resume running some time after 100 milliseconds have elapsed.
A monitor called mon has 10 threads in its waiting pool; all these waiting threads have the same priority.  One of the threads  is thr1. How can you notify thr1 so that it alone moves from the Waiting state to the Ready state? | you cannot  specify which thread  will get notified.
class  TestThread3 extends Thread | yes
A Java monitor must either extend Thread or implement  Runnable. | fasle
Which of the following methods  in the Thread class are deprecated | suspend() and resume()
Which of the following statements  about  threads  is true? | threads  inherit their priority  from their parent  thread.
Threads  inherit their priority  from their parent  thread. | the thread  that calls wait() goes into the monitor’s  pool of waiting threads.
The thread  that calls wait() goes into the monitor’s  pool of waiting threads. | classes
Which of the following calls may be made from a non-static synchronized method? | all
is it possible to write code that can execute only if the current  thread  owns multiple locks? | yes
Which of the following are true? (Choose all that apply.) | there is one non-daemon thread - a thread  created by a daemon  thread  - a thread  created by a non-daemon thread
How can you ensure that multithreaded code does not deadlock | a, b, and c do not ensure that multithreaded code does not deadlock.
Which of the following are true? (Choose all that apply | when you declare a method to be synchronized, the method - when you declare a block of code inside a method  to be synchronized, you can
Suppose you want to create a custom thread  class by extending  java.lang.Thread in order to provide some special functionality. Which of the following must you do? | override  run().
Given a string constructed by calling s = new String(“xyzzy”), which of the calls modifies the string? | none of the above
String s1  = “abc” + “def”; | line 6 executes and line 4 does not.
Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions.  You decide to subclass java.lang.Math and provide the new functionality as a set of static methods.  Which one statement is true about  this strategy | the strategy fails because you cannot  subclass java.lang.math
import java.lang.Math; | compilation fails at line 2.
String s = “abcde”; | compilation succeeds. no exception  is thrown during execution.
StringBuffer  sbuf = new StringBuffer(“abcde”); | true
String s1  = “xyz”; String s2  = “xyz”; | true
String s1  = “xyz”; String s2  = new String(s1); | false
Suppose prim  is an int and wrapped is an Integer. Which of the following are legal Java statements? (Choose all that  apply.) | prim   =  wrapped; - wrapped =  prim; - prim   =  new integer(9); - wrapped =  9;
Which of the following are legal? (Choose all that apply.) | list<string> thelist  =  new vector<string>(); - vector <string>  thevec =  new vector<string>();
Map<String> names  = new HashMap<String>(); | iterator<string> iter =  names.iterator(); - for (string s:names)
Which of the following are legal clone() methods  in a class called Q13 that extends Object | public object clone() throws clonenotsupportedexception {  return super.clone();  } - d.	public q13 clone() throws clonenotsupportedexception {  return  (q13)super.clone();  }
Which of the following classes implement  java.util.List | java.util.arraylist - java.util.stack
Which of the following are methods  of the java.util.SortedSet interface? | first - last - headset - tailset - subset
Which of the following are methods  of the java.util.SortedMap interface? | headmap- tailmap - submap
Which line of code tells a scanner called sc to use a single digit as a delimiter? | sc.usedelimiter(“\\d”);
public class Apple | an exception  is thrown at line 7.
Given arrays a1 and a2, which call returns  true if a1 and a2 have the same length, and a1[i].equals(a2[i]) for every legal index i? | java.util.arrays.equals(a1, a2);
Which of the following statements  are true? | stringbuilder is generally faster than stringbuffer. - stringbuilder is generally faster than stringbuffer.
Which of the statements  below are true? (Choose all that apply | unicode characters are all 16 bits.
Which of the statements  below are true? (Choose all that apply.) | none of the above.
How do you use the File class to list the contents  of a directory? | string[]  contents =  myfile.list();
How many bytes does the following code write to file dest? | 12
FileOutputStream fos = new FileOutputStream(“xx”); | the output is i = 20.
FileOutputStream fos = new FileOutputStream(“datafile”); | construct a fileinputstream - construct a randomaccessfile,
Which of the following is true about Readers have methods  that can read ? | none of the above
File f1 = new File(“dirname”); | no directory  is created,  and no file is created.
Assume that the code fragment is part of an application that has write permission in the current working directory.  Also assume that before execution,  the current  working  directory  does not contain  a file called datafile. | the code fails to compile
Suppose you are writing a class that will provide custom serialization. The class implements java.io.Serializable (not java.io.Externalizable). What access mode should the writeObject() method  have? | private
Suppose you are writing a class that will provide custom deserialization. The class implements java.io.Serializable (not java.io.Externalizable). What  access mode should  the readObject() method  have? | private
Suppose class A extends Object; class B extends A; and class C extends B. Of these, only class C implements java.io.Serializable. Which of the following must be true in order to avoid an exception  during deserialization of an instance of C? | b must have a no-args constructor.
Suppose class A extends Object; Class B extends A; and class C extends B. Of these, only class C implements java.io.Externalizable. Which of the following must be true in order to avoid an exception  during deserialization of an instance of C? | c must have a no-args constructor.
public class Xyz implements java.io.Serializable | iampublic - iamprivate - iamvolatile
What method  of the java.io.File class can create a file on the hard drive | createnewfile()
public class Xxx | an exception  is thrown at line 9.
Which of the following are valid mode strings for the RandomAccessFile constructor? (Choose all that apply.) | r - rw - rws - rwd
Which of the following are valid arguments  to the DataInputStream constructor? | fileinputstream
public enum Wallpaper | wallpaper wp =  wallpaper.blue; - void  amethod(wallpaper wp)  { system.out.println(wp);} - int hcode   = wallpaper.blue.hashcode();
class  Sploo | b - d - fff()
public abstract class Abby | subabby generates a compiler error. - if subabby were declared abstract, it would compile without error. - abby is a legal type for variables.
class Xxx | heights is initialized to a reference to an array with zero elements
Given a class with a public variable theTint of type Color, which of the following methods are consistent  with the JavaBeans naming standards? | public color getthetint()
Which of the following statements  are true regarding  the following method? void  callMe(String… names) {  } | within  the method,  names is an array containing  strings.
public class Food | fruit - citrus - pomelo
class A  extends java.util.Vector | the compiler does not create a default constructor.
Which of the following types are legal arguments  of a switch statement | enums - bytes
int[]  ages = {  9, 41, 49  }; int sum = 0; | for (int  i=0; i<ages.length; i++) sum += ages[i]; - for (int i:ages) sum += i;
Which lines check that x is equal to four? Assume assertions  are enabled at compile time and runtime. | assert x  == 4; - assert   x  == 4  : “x  is not 4”;
Which are appropriate uses of assertions | checking preconditions in a private method - checking postconditions in a private method - checking postconditions in a public method
void callMe()  throws ObjectStreamException | void callme() - void callme() throws notserializableexception
NotSerializableException extends ObjectStreamException. AWTException does not extend any of these. All are checked exceptions.  The callMe() method  throws  NotSerializableException | object stream - finally
While testing some code that you are developing,  you notice that an ArrayIndexOutOf- BoundsException is thrown. What is the appropriate reaction? | none of the above
How is IllegalArgumentException used? (Choose all correct options.) | it is thrown by certain methods - it should be used by programmers to indicate that preconditions of public
Suppose shorty is a short and wrapped is a Short. Which of the following are legal Java state- ments? (Choose all correct options.) | shorty =  wrapped; - wrapped =  shorty; - shorty =  new short((short)9); - shorty =  9;
Which of the following statements  are true? (Choose all correct options.) | stringbuilder encapsulates a mutable  string. - stringbuffer is threadsafe.
The file contains  lines of 8-bit text, and the 8-bit encoding represents the local character set, as represented by the cur- rent default locale | create a filereader instance.  pass it into the constructor of linenumberreader. use linenumberreader’s readline()  method.
What interfaces can be implemented in order to create a class that can be serialized? (Choose all that apply.) | java.io.serializable. there are no methods - java.io.externalizable, which defines two methods:  readexternal
Suppose you want to create a class that compiles and can be serialized and deserialized without causing an exception  to be thrown. Which statements  are true regarding  the class? (Choose all correct options.) | java.io.externalizable, it must have a no-args - java.io.serializable and does not implement
Suppose you want to use a DateFormat to format  an instance of Date.  What factors influence the string returned by DateFormat’s format() method? | the style, which is one of short, medium, long, or full - the locale
How do you generate a string representing  the value of a float f in a format  appropriate for a locale loc? | numberformat   nf = numberformat.getinstance(loc);
String scanMe  = “aeiou9876543210AEIOU”; | string  delim =  “\\d+”;
Suppose MyThread extends java.lang.Thread, and MyRunnable implements  java.lang.Runnable (but does not extend Thread). Both classes have no-args constructors. Which of the following cause a thread  in the JVM to begin execution?  (Choose all correct options.) | (new  mythread()).start(); - (new  thread(new myrunnable()))
(new  Thread(new MyRunnable())) | the code prints “going  to sleep,” then “waking up,”  and then “all done.”
Suppose threads  aThread and bThread are both accessing a shared object named sharedOb, and aThread has just executed: sharedOb.wait(); | athread.interrupt(); - sharedob.notifyall();
Suppose class Home has methods  chopWood() and carryWater(); it also has a method  called chopWoodAndCarryWater(), which just calls the other two methods.  Which statements  are true? (Choose all that apply.) | chopwoodandcarrywater() is an example of inappropriate cohesion. - chopwoodandcarrywater() is an example of inappropriate coupling.
Lemon lem  = new Lemon(); Citrus cit = new Citrus(); | cit =  lem; - lem  =  (lemon)cit; - cit =  (citrus)lem;
Grapefruit g  = new Grapefruit(); | the cast in line 2 is not necessary. - the cast in line 2 is not necessary.
Suppose class aaa.Aaa has a method called callMe(). Suppose class bbb.Bbb, which extends aaa.AAA, wants  to override callMe(). Which access modes for callMe() in aaa.AAA will allow this? | public - protected
class Animal | class zebra generates a compiler error
class Xyz | super(); - this(1.23f);
What relationship does the extends keyword  represent? | is a
When should objects stored in a Set implement  the java.util.Comparable interface | when the set is a treeset
class Xyzzy | public  int  hashcode() {  return a;  } - public  int  hashcode() { return  (int)math.random();}
plainVec; Vector<String>  fancyVec; | attempting to add anything  other than a string to fancyvec results in a compiler error.
The declaration of the java.util.Collection interface is interface  Collection <E> | public  boolean addall(collection<?  extends e> c)
package ocean; public class Fish | public void swim() { } - size =  12;
public class App | 4
public class Wrapper | n is 10, w.x  is 11
String s = “aaa”; | after line 3
java -classpath  somewhere;elsewhere aaa.bbb.MyApplication | class myapplication must contain  the statement package  aaa.bbb;. - d.	the file myapplication.class must be found either in somewhere\aaa\bbb or in elsewhere\aaa\bbb. (substitute  forward slashes for backslashes  on a unix system
drivers that implement the JDBC API as a mapping to another data access API, such as ODBC. Drivers of this type are generally | type 1
public class A | line 26 prints “a” to system.out.
public class A | the code on line 29 will be executed. - the exception will be propagated back to line 27.
try { | bad url - doing finally part - carrying on
interface Foo | the code compiles and the output is 2. - if lines 16, 17 and 18 were removed, the code would compile and the output would be 2. - if lines 24, 25 and 26 were removed, the code would compile and the output would be 1.
public class ClassA | an exception is thrown at runtime
public class Bootchy | third second first snootchy 420
A  	 dialog prevents user input to other windows in the application unitl the dialog is closed. | modal
A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these | public void logit(string... msgs)
try { | at line 2, the thread will stop running. it will resume running some time after 100 milliseconds have elapsed
A(n)  	 object is used to submit a query to a database | statement
A(n)  	 object is uses to obtain a Connection to a Database | drivermanager
public class Money | euro returns correct country value. - compilation fails because of an error at line 25
public class SomeException | compilation of class b will fail. compilation of class a will succeed
public class TestException extends Exception | line 46 will compile if the enclosing - line 46 will compile if enclosed.
public class Test extends Base | test t = new test(1); - test t = new test(1, 2);
public class Test extends Base | base() { } - base(int j, int k) { }
class Cruncher | the code will compile and produce the following output: int version
Object ob = new Object(); | line 6
public class Assertification | the application must be - the args array must have one or more elements.
StringBuffer sbuf = new StringBuffer(); | after line 2 executes, the stringbuffer object is eligible for garbage collection.
Cat sunflower; | the code will compile but will throw an exception at line 7, because the runtime class of wawa cannot be converted to type swampthing.
Select INCORRECT statement about  serialization. (choose 1 | when an object output stream serializes an object that contains references to another object, every referenced object is not serialized along with the original object
Select incorrect statement about RMI server.(choose 1) | a client accesses a remote object by specifying only the server name
Select the correct statement about JDBC two-tier processing model | a user's commands are delivered to the database or other data source, and the results of those statements are sent back to the user.
SQL keyword  	 is followed by the selection criteria that specify the rows to select in a query | where
Statement objects return SQL query results as  	 objects | resultset
When a JDBC connection is created, it is in auto-commit mode 2)Once auto-commit mode is disabled, no SQL statements will be committed until you call the method commit explicitly | both 1 and 2 are true suppose a method called finallytest() consists of a try block, followed by a catch block, followed by a finally block. assuming the jvm doesn’t crash and the code does not execute a system.exit() call, under what circumstances will the finally block not begin to execute?  |  If the JVM doesn't crash and the code does not execute a System.exit() call,the finally block will always execute.
Suppose a source file contains a large number of import statements. How do the imports affect the time required to compile the source file? (Choose one. | suppose a source file contains a large number of import statements. how do the imports affect the time required to compile the source file? (choose one.)
Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides doSomething(). What access modes may Subby’s version of the method have? (Choose two.) | public - protected
Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions. You decide to subclass java.lang.Math and provide the new functionality as a set of static methods. Which one | the strategy fails because you cannot add static methods to a subclass.
The  	 class is the primary class that has the driver information. | drivermanager
The  	 class is used to implement a pull-down menu that provides a number of items to select from. | menu
The Swing component classes can be found in the  	package. | javax.swing
public class Bird | compilation of parrot.java fails at line 7 because method getrefcount() is static in the superclass, and static methods may not be overridden to be nonstatic.
public class Bird | the program will compile and execute. the output will be before: 0 after: 2.
What are the legal types for whatsMyType? (Choose one.) short s = 10;whatsMyType = !s; | there are no possible legal types.
What does the following code do? Integer i = null; if (i != null & i.intValue() == 5) System.out.println("Value is 5"); | throws an exception.
FileOutputStream fos = new FileOutputStream("xx"); | the output is i = 20.
public class Xxx | an exception is thrown at line 9.
public class Q | the code compiles, and prints out >>null<<
public class Apple | an exception is thrown at line 7.
final class Aaa | on line 1, remove the final modifier.  |  On line 1, remove the final modifier.
What is the result of attempting to compile and execute the following code fragment? Assume that the code fragment is part of an application that has write permission in the current working directory. Also assume that before execution, the current working directory does not contain a file called datafile. (Choose one.) | the code fails to compile.
The code fails to compile. | a boolean
public class Conditional | the output: value is 9.0
public class Xor | the output: b contains 5.
int x = 0, y = 4, z = 5; | message four
When does an exception's stack trace get recorded in the exception object?(Choose one.) | when the exception is constructed
When is it appropriate to pass a cause to an exception's constructor?(Choose one.) | when the exception is being thrown in response to catching of a different exception type
When the user attempts to close the frame window,  	 event in generated. | window closing
When the user selects a menu item,  	 event is generated. | action event
Whenever a method does not want to handle exceptions using the try block, the  	 is used. | throws
Which are the correct statements used for getting connection object to connect to SQL Server database? | string url ="jdbc:odbc:data_source_name"; connection con = drivermanager.getconnection (url, “user", "password");
Which class and static method can you use to convert an array to a List? (Choose one.) | arrays.aslist
Which is four-step approach to help you organize your GUI thinking. (Choose one.) | identify needed components. isolate regions of behavior. sketch the gui. choose layout managers.
Which is the four steps are used in working with JDBC? | 1)connect to the database 2)create a statement and execute the query 3)look at the result set 4)close connection
Which methods return an enum constant’s name? (Choose two.) | name() which modifier or modifiers should be used to denote a variable that should not be written out as part of its class's persistent state? (choose the shortest possible answer.) tostring()  |  transient
Which of the following are legal argument types for a switch statement? (Choose three.) | byte - int - char
Which of the following are legal import statements? (Choose two.) | import java.util.vector; - import static java.util.vector.*;
Which of the following are legal loop constructions? (Choose one.) | int j = 0; for (int k=0, j+k != 10; j++,k++) { system.out.println("j=" + j + ", k=" + k); }
Which of the following are legal? (Choose three.) | for (int i=0, j=1; i<10; i++, j++) - for (int i=0, j=1;; i++, j++) - for (string s = ""; s.length()<10; s += '!')
Which of the following are legal? (Choose two.) | double d = 1.2d; double d = 1.2d;
Which of the following are legal? (Choose two.) | int c = 0xabcd; int d = 0xabcd;
Which of the following are legal? (Choose two.) | char c = 0x1234; - char c = '\u1234';
Which of the following are legal? (Choose two.) | list<string> thelist = new vector<string>(); - list<string> thelist = new vector<string>();
Which of the following are methods of the java.util.SortedMap interface? (Choose three.) | headmap - tailmap - submap
Which of the following are true? (Choose two.) | when you declare a method to be synchronized, the method -  to be synchronized, you can specify the
Which of the following are true? (Choose two.) | an enum may contain public method definitions. - an enum may contain private data.
Which of the following are true? (Choose two.) | primitives are passed by value. - references are passed by value.
Which of the following are true? (Choose two.) | an anonymous inner class may implement at most one interface. - an anonymous inner class may extend a parent class other than object.
Which of the following classes implement java.util.List? (Choose two.) | java.util.arraylist - java.util.stack
Which of the following declarations are illegal? (Choose three.) | default string s; - abstract double d; - abstract final double hyperboliccosine();
Which of the following expressions are legal? (Choose two.) | int x = 6; if (!(x > 3)) {} - int x = 6; x = ~x;
Which of the following expressions are legal? (Choose two.) | string x = "hello"; int y = 9; x += y; - string x = "hello"; int y = 9; x = x + y;
Which of the following interfaces does not allow duplicate objects? (Choose one.) | set
Which of the following interfaces does not allow duplicate objects? (Choose one.) | preconditions of a public method
Which of the following may appear on the right-hand side of an instance of operator? (Choose two.) | a class - an interface
Which of the following may be declared final? (Choose two.) | classes - methods
Which of the following may be statically imported? (Choose two.) | static method names - static field names
Which of the following may follow the static keyword? (Choose three.) | data - methods - code blocks enclosed in curly brackets
Which of the following may override a method whose signature is void xyz(float f)? (Choose two.) | void xyz(float f) - public void xyz(float f)
Which of the following signatures are valid for the main() method entry point of an application? (Choose two.) | public static void main(string arg[]) - public static void main(string[] args)
Which of the following statements are true? (Choose one.) | a final class may not be extended
Which of the following statements are true? (Choose two.) | stringbuilder is generally faster than stringbuffer. - stringbuffer is threadsafe; stringbuilder is not.
Which of the following statements are true? 1)An abstract class may not have any final methods. 2)A final class may not have any abstract methods. | only statement 2
byte b = 5; 2. char c = ‘5’; | line 6
class HiPri extends Thread | none of the above scenarios can be guaranteed to happen in all cases.
String s = "FPT"; | compilation succeeds. no exception is thrown during execution.
String s1 = "abc" + "def"; | line 6 executes and line 4 does not.
class Greebo extends java.util.Vector  implements Runnable | there will be a compiler error, because class greebo does not correctly implement the runnable interface.
Which statement is true about the following method? int selfXor(int i) { return i ^ i; } | it always returns 0.
class StaticStuff | the code compiles and execution produces the output x = 3.
Which statements about JDBC are NOT true? (choose 2) | jdbc is a java  database system. jdbc is a java api for connecting to any kind of dbms
Which two code fragments correctly create and initialize a static array  of int elements? (Choose two.) | static final int[] a = { 100,200 }; - static final int[] a; static { a=new int[2]; a[0]=100; a[1]=200; }
Which two of the following interfaces are at the top of the hierarchies in the Java Collections Framework?  (Choose two.) | map - collection
You execute the following code in an empty directory. What is the result? (Choose one.) 1. File f1 = new File("dirname"); 2. File f2 = new File(f1, "filename"); | no directory is created, and no file is created.
"A pet has an owner, a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating if it has been neutered, and a textual description of its markings." | public class cat extends pet
"A pet has an owner, a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating whether it has been neutered, and a textual description of its markings." | boolean neutered; - string markings;
public class Pass | dostuff x = 5 main x = 5
which of the following is incorrect | when an application begins running, there is one deamon thread
public class test1 | public float amethod(float x, float y){}
which of the following statements is true about two base protocols used for networking:TPC and UDP | tpc is a connection-based protocol and udp is not connec
public class Main | the program has a compile error
which method do you see to enable or disable components such as jbuttons | enable()
which of following methods of the java.io.file can be used to check whether a file can be read or not | canread()
which statements about jdbc are not true | jdbc is a java api for connecting to any kind of dbms - is a java database system
with respect to stops in RMI implementation | create interface - create object - create stub- create client
the   class is primary clas that has the driver information | drivermanager
select a correct statement | datainputstream, dataoutputstream are binary streams
select incorrect statement about remote class | it must extend java.rmi.server.unicastremoteobject
the container can display three completely different components at different times, depending perhaps on user input | cardlayout
public class Mine | no such file found, doing finally; -1
which to of the following interfaces are at the top of the hierarchies in the java collections framework | collection - map
a    dialog prevents user input to other windows in the application until the dialog is closed | modal
which of the followings statements is true | rows and columns ins a gridbaglayout can have different sizes
public class main | line 17 is never executed
which of the following statements is true | in the networking with client-server model, the server computer has a socket ...also need
swing is part of the java foundation classes and provides a rich set of gui components | none of the others
fileoutputstream fos = new fileoutputstream("dest") | 12
public class setF extends frame | s.setbackground(color.pink)
which of the following layout manager will present components with the same size | java.awt.gridlayour
the default type of the resultset object is | type_forward_only
public class main | line 17 throws an exception at runtime
select incorrect statement about remote class | it must extend java.rmi.server. remoteobject
how can you change the current working directory using an instance of the file class called filename | the file class does not support directly changing the current directory
in a client-server application model, which sides will initiate a connection | server
public class Mod | error at compilation: native method cannot be static
select the correct result of the expression: 5 >>> 1 | 2
class InOut | system.out.println(iargs); - system.out.println(s);
which of the following methods of the java.io.File can be used to create a new file | createnewfile()
Which of the following about Reader class is true | reader has method that can read a single character
which of the following is true | the >> operator carries the sign bit when shifting right. the >>> zero-fills bits that have been shifted out
what is the difference between yielding and sleeping | when a task invokes its yield() method, it returns to the ready state.
class base | runtime exception
which of the followings is incorrect | when an application begins running, there is one deamon thread
which of the following is not an example pf a data type | public
which if the following is true | you cannot call enum's to string() method
what must a class do to implement an interface | it must provide all of the methods in the interface and identify the interface in its implements clause
all of the numeric wrapper classes in the java.lang package are subclasses of the abstract class | java.lang.number
which of the following modifiers does not allow a variable to be modified its value once it was initialized | final
public static void main | the program will run and output only "fliton"
RMI applications often often comprise two separate programs, a server and a client and they | can run in two separate machine
abstract class minebase | error mine must be declared abstract
which of the following is true about Wrapped classes | wrapped classes are classes that allow primitive types to be accessed as objects
if(check4Biz(storeNum)!= null){} | boolean - string
for a class defined inside a method, what rule governs access to the variables of the enclosing method | the class can only access final variables
select the correct syntax for throwing an exception when declaring a method | [modifier] {return type] indentifier (parameters) throws typeofexception
in RMI implementations, all methods, declared in the remote interface, must throw the    exception | java.rmi.remoteexception
public class Funcs extends java.lang.math | the line 10 causes compile-time error
which of the following statements is true about a variable created with the static modifier | a static variable created in a method will keep the same value between calls
try { | ac
what will happen if you try to compile and run the following code | 2
line.point p = new line.point(); | true
base(){} base (intj,int k){} | true
foo(count); | 1
suppose the declared type of x is a class | when the type of x is object
A method in an interface can access class level | true
double d = 1.2d | true
Access the variables only via synchronized methods | true
the swing's list + the swing's label | true
which of the following operations might throw an arithmetic exception | %
under no circumstances + adding more classes | true
a protected method may only be accessed by classes of the same | true
vector does not allow duplicate elements | true
datainputstream | fileinputstream
the program cause errors when it is compiled | true
tcp is a connection-based protocol | true
to check whether the file denoted by the abstract | true
what is the output when you try to compile and run the | equal
we don't need any method because elements in vector are automatically sorted | true
setlayout(new flowlayout()); | true
for (float f:salaries) | true
a runtime error indicating that no run method | true
if(s.equalIgnoreCase(s2)) | true
output one one two two | true
String x = *Hello*. int y = 9;x= x+ y | true
the compiler will compalin that the base class is not declared as abstract | true
No compiler error and no exception | class a
you can not call an enum's to string | true
creatnewfile() | true
given a string constructed by calling s = new String("xyzzy") | none of the other
b=m; | class base{}
cannot call to a static synchonized method | true
How can you force garbage collection of an object | garbage collection cannot be force
char c = \u1234 | true
boderlayout is the default layout manager | true
if(s.equalsIgnoreCase(s2)) | true
int x = 6; x =~x | true
Wrapper classes are: Boolean, Char, Byte, Short, Integer, Long, Float and Double | true
The GridBagLayout managet is the default manager for JFame | true
When you construct an instance of File, the file will bot be created even if the corresponding file does not exist on the | true
public interface B instanceOf A {} | true
A for statement can loop infinitely, for example: for(;;); | true
a # b; a == c | true
How many strings, specified by the above code, are stored in the memory of the program? | 2
What is the difference between a TextArea and a TextField? | a textarea can handle multiple lines of text
You have been given a design document for a veterinary registration system for implementation in Java. It states: | string markings; boolean neutered
3. Which of the following expressions results in a positive value in x? | int x = -1; x = x >>> 5;
4. Which of the following expressions are legal? | (choose all that apply.)a. string x = "hello"; int y = 9; x += y;c. string x = "hello"; int y = 9; x = x + y;
5.Is it possible to define a class called Thing so that the following method can return true under certain circumstances?boolean weird(Thing s) { Integer x = new Integer(5); return s.equals(x);} | yes
6.Suppose ob1 and ob2 are references to instances of java.lang.Object. If (ob1 == ob2) isfalse, can ob1.equals(ob2) ever be true? | b. no
13. When a short is added to a float, what is the type of the result? | c. float
14. Which statement is true about the following method?int selfXor(int i) { return i ^ i;} | a. it always returns 0.
15. Which of the following operations might throw an ArithmeticException? | d. none of these
16. Which of the following operations might throw an ArithmeticException? | d. /
17. What is the return type of the instanceof operator? | d. aboolean
18. Which of the following may appear on the left-hand side of an instanceof operator? | a. a reference
19. Which of the following may appear on the right-hand side of an instanceof operator? (Choose all that apply.) | b. a classc. an interface
20. What is -50 >> 1? | d. -25
1. Which of the following declarations are illegal? (Choose all that apply.) | a. default string s;d. abstract double d;e. abstract final double hyperboliccosine();
2. Which of the following statements is true? | b. a final class may not have any abstract methods.
4. Which of the following statements is true? | e. transient variables are not serialized.
5. Which statement is true about this application?1. classStaticStuff2 {3. static int x = 10; 4.5. static { x += 5; }6.7. public static void main(String args[])8. {9.System.out.println("x = " + x);10. } 11.12. static {x /= 5;}13. } | e. the code compiles and execution produces theoutput x = 3.
6. Which statement is true about this code?1. class HasStatic2. {3. private static int x = 100; 4.5. public static void main(String args[])6. {7. HasStatic hs1 = new HasStatic();8. hs1.x++;9. HasStatic hs2 = new HasStatic();10. hs2.x++;11. hs1 = new HasStatic();12. hs1.x++;13. HasStatic.x++;14. System.out.println("x = " + x);15. } 16. } | e. the program compiles and the output isx=104.
7. Given the following code, and making no other changes,which combination of access modifiers (public, protected,or private) can legally be placed before aMethod() on line3and be placed before aMethod() on line 8?1. class SuperDuper2. {3. void aMethod() { }4. } 5.6. class Sub extends SuperDuper7. {8. void aMethod() { }9. } | d. line 3: private; line 8: protectedwhich statement is true about class bird and the following class nightingale?1. package singers; 2.3. class nightingale extends abcde.bird {4. nightingale() { referencecount++; } 5.6. public static void main(string args[]) {7. system.out.print("before: " + referencecount);8. nightingale florence = new nightingale();9. system.out.println(" after: " + referencecount);10. florence.fly();11. }12. }  |  A. The program will compile and execute. The output will be Before: 0 After: 2.
11. Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides doSomething(). What access modes may Subby's version of the method have? (Choose all that apply.) | a. publicb. protected
Inty but does not provide implementations for any of the five interface methods. Which is/are true? | c. the class will compile if it is declared abstract.d. the class may not be instantiated.
15. Which of the following may follow the static keyword? (Choose all that apply.) | b. datac. methodsd. code blocks enclosed in curly brackets
16. Suppose class A has a method called doSomething(), with default access. Suppose class B extends A and overrides doSomething(). Which access modes may apply to B's version of doSomething()? (Choose all that apply.) | a. publicc. protectedd. default
17. True or false: If class Y extends class X, the two classes are in different packages, and class X has a protected method called abby(), then any instance of Y may call the abby() method of any other instance of Y. | b. false
4. In the following code, what are the possible types for variable result? (Choose the most complete true answer.)1. byte b = 11;2. short s = 13;3. result = b * ++s; | e. int, long,float, double
5. Consider the following class:1. class Cruncher {2. void crunch(int i) {3. System.out.println("int version");4. }5. void crunch(String s) {6. System.out.println("String version");7. } 8.9. public static void main(String args[]) {10. Cruncher crun = new Cruncher();11. char ch = 'p';12. crun.crunch(ch);13. }14. }Which of the following statements is true? (Choose one.) | d. the code will compile and produce the following output: int version.
8. Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class's persistent state? (Choose the shortest possible answer.) | d. transient
19. Which of the following statements are true? | d. a final class may not be extended.
10. Consider the following code:1. Raccoon rocky;2. SwampThing pogo;3. Washer w; 4.5. rocky = new Raccoon();6. w = rocky;7. pogo = w;Which of the following statements is true? (Choose one.) | b. line 7 will not compile; an explicit cast is required to convert a washer to a swampthing.
11. Which of the following may legally appear as the new type (between the parentheses) in a cast operation? | e. all of the above
14. Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment xarr = yarr; legal? | a. sometimes
17. When a negative long is cast to a byte, what are the possible values of the result? | d. all of the above
19. Which of the following operators can perform promotion on their operands? (Choose all that apply.) | a. +b. -e. ~
20. What is the difference between the rules for method-call conversion and the rules for assignment conversion? | a. there is no difference; the rules are the same.
You have been given a design document for a veterinary registrationsystem for implementation in Java. It states:"A pet has an owner, a registration date, and a vaccination-due date. A catis a pet that has a flag indicating whether it has been neutered, and a textual description of its markings."Given that the Pet class has already been defined, which of the following fields would be appropriate for inclusion in the Cat class as members? (Choose two.) | e. boolean neutered;f. string markings;
Given that the Pet class has already been defined and you expect the Cat class to be used freely throughout the application, how would you make the opening declaration of the Cat class, upto but not including the first opening brace? Use only these words and spaces: boolean, Cat, class, Date, extends, Object, Owner, Pet, private, protected, public, String.(Choose one.) | public class cat extends pet
(241) You execute the following code in an empty directory. What is the result?(Choose one.)1. File f1 = new File("dirname");2. File f2 = new File(f1, "filename"); | e. no directory is created, and no file is created.
(1873) Which two of the following interfaces are at the top of the hierarchies inthe Java Collections Framework? (Choose two.) | b. mape. collection
(1423) Which two code fragments correctly create and initialize a static array ofint elements? (Choose two.) | a. static final int[] a = { 100,200 };b. static final int[] a; static { a=new int[2]; a[0]=100;a[1]=200; }
(4929) Which statements about JDBC are NOT true? (choose 2) | e. jdbc is a java database system.f. jdbc is a java api for connecting to any kind of dbms
Which statement is true about this code? (Choose one.)1. class HasStatic2. {3. private static int x = 100;4.5. public static void main(String args[])6. {7. HasStatic hs1 = new HasStatic();8. hs1.x++;9. HasStatic hs2 = new HasStatic();10. hs2.x++;11. hs1 = new HasStatic();12. hs1.x++; 13. HasStatic.x++;14. System.out.println("x = " + x);15. }16. } | e. the program compiles and the output is x = 104.
int selfXor(int i) {return i ^ i;} | a. it always returns 0.
(151) Which statement is true about the following code fragment? (Choose one.)1. int j = 2;2. switch (j) {3. case 2:4. System.out.println("value is two");5. case 2 + 1:6. System.out.println("value is three");7. break;8. default:9. System.out.println("value is " j);10.break;11. } | d. the output would be the text value is two followed by the text value is
(192) Which one statement is true concerning the following code1. class Greebo extends java.util.Vector implements Runnable {2.3. public void run(String message) {4. System.out.println("in run() method: " + message);5.6. }7. }8.9. class GreeboTest {10. public static void main(String args[]) {12. Greebo g = new Greebo();13. Thread t = new Thread(g);14. t.start();15. }16. } | a. there will be a compiler error, because class greebo does not correctlyimplement the runnable interface.
Which one statement is true about the following code?1. String s1 = "abc" + "def"; 2. String s2 = new String(s1);3. if (s1 == s2)4. System.out.println("== succeeded");5. if (s1.equals(s2))6. System.out.println(".equals() succeeded"); | c. line 6 executes and line 4 does not.
(216) Which one statement is true about the following code fragment?1. String s = "FPT";2. StringBuffer s1 = new StringBuffer("FPT");3. if (s.equals(s1))4. s1 = null;5. if (s1.equals(s))6. s = null | e. compilation succeeds. no exception is thrown during execution.
(215) Which one statement is true about the following code fragment? (choose 1)1. import java.lang.Math;2. Math myMath = new Math();3. System.out.println("cosine of 0.123 = " + myMath.cos(0.123)); | a. compilation fails at line 2.
(193) Which one statement is always true about the following application?1. class HiPri extends Thread {2. HiPri() {3. setPriority(10);4. }5.6. public void run() {7. System.out.println(8. "Another thread starting up.");9. while (true) { }10. }11.12. public static void main(String args[]) {13. HiPri hp1 = new HiPri();14. HiPri hp2 = new HiPri();15. HiPri hp3 = new HiPri();16. hp1.start();17. hp2.start();18. hp3.start();19. }20. } | d. none of the above scenarios can be guaranteed to happen in all cases.
(128) Which one line in the following code will not compile?1. byte b = 5;2. char c = '5';3. short s = 55;4. int i = 555;5. float f = 555.5f;6. b = s;7. i = c;8. if (f > b)9. f = i; | f. line 6
(234) Which of the statements below are true? (Choose one.) | d. none of the above.
(235) Which of the statements below are true? (Choose one.) | d. none of the above
(132) Which of the following statements is true? (Choose one.) | d. object references can be converted in both method calls and assignments,
(127) Which of the following statements is correct? (Choose one.) | d. both primitives and object references can be both converted and cast.
(108) Which of the following statements are true?1)An abstract class may not have any final methods.2)A finalclass may not have any abstract methods. | b. only statement 2
(232) Which of the following statements are true? (Choose two.) | a. stringbuilder is generally faster than stringbuffer.d. stringbuffer is threadsafe; stringbuilder is not.
(118) Which of the following statements are true? (Choose one.) | f. none of the above
(176) Which of the following statements are true? (Choose one.) | a. given that inner is a nonstatic class declared inside a public class outerand that appropriate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
(125) Which of the following statements are true? (Choose one. | d. a final class may not be extended.
(200) Which of the following statements about threads is true? (Choose one.) | b. threads inherit their priority from their parent thread.
(201) Which of the following statements about the wait() and notify() methods is true? (Choose one.) | c. the thread that calls wait() goes into the monitor's pool of waiting threads.
(47) Which of the following signatures are valid for the main() method entrypoint of an application? (Choose two.) | b. public static void main(string arg[])d. public static void main(string[] args)
(145) Which of the following operators can perform promotion on theiroperands? (Choose three.) | a. +b. -e. ~
(82) Which of the following operations might throw an ArithmeticException? (Choose one.) | d. /
(81) Which of the following operations might throw an ArithmeticException?(Choose one.) | d. none of these
(199) Which of the following methods in the Thread class are deprecated?(Choose one.) | a. suspend() and resume()
(186) Which of the following may override a method whose signature is voidxyz(float f)? (Choose two.) | a. voidxyz(float f)b. public void xyz(float f)
(202) Which of the following may not be synchronized? (Choose one.) | d. classes
(137) Which of the following may legally appear as the new type (between theparentheses) in a cast operation?(Choose one.) | e. all of the others
(121) Which of the following may follow the static keyword? (Choose three.) | b. datac. methodsd. code blocks enclosed in curly brackets
(58) Which of the following may be statically imported? (Choose two.) | b. static method namesc. static field names
(120) Which of the following may be declared final? (Choose two.) | a. classesc. methods
(85) Which of the following may appear on the right-hand side of an instanceofoperator? (Choose two.) | b. a classc. an interface
(184) Which of the following is(are) true? (Choose one.)a. An enum definition may contain the main() method of an application. | e. all the above
(240) Which of the following is true? (Choose one.) | e. none of the above
(5695) Which of the following is NOTa valid comment: | c. /* comment
(1874) Which of the following interfaces does not allow duplicate objects?(Choose one.) | b. set
(69) Which of the following expressions results in a positive value in x?(Choose one.) | a. int x = -1; x = x >>> 5;qn=216
(70) Which of the following expressions are legal? (Choose two.) | a. string x = "hello"; int y = 9; x += y;c. string x = "hello"; int y = 9; x = x + y;
(68) Which of the following expressions are legal? (Choose two.) | b. int x = 6; if (!(x > 3)) {}c. int x = 6; x = ~x;
(107) Which of the following declarations are illegal? (Choose three.) | a. default string s;d. abstract double d;e. abstract final double hyperboliccosine();
(1878) Which of the following classes implements a FIFO Queue? (Choose one.) | b. linkedlist
(203) Which of the following calls may be made from a non-static synchronizedmethod? (Choose one.) | e. all the above
(252) Which of the following are valid mode strings for the RandomAccessFile constructor? (Choose one.) | e. all the above
(253) Which of the following are valid arguments to the DataInputStreamconstructor? (Choose one.) | c. fileinputstream
(188) Which of the following are true? (Choose two.) | a. an anonymous inner class may implement at most one interface.c. an anonymous inner class may extend a parent class other than object.
(65) Which of the following are true? (Choose two.) | b. primitives are passed by value.d. references are passed by value.
(185) Which of the following are true? (Choose two.)m. | c. an enum may contain public method definitions.d. an enum may contain private data.
(210) Which of the following are true? (Choose two.) | a. when you declare a method to be synchronized, the method alwayssynchronizes on the lock of the current object.d. when you declare a block of code inside a method to be synchronized, youcan specify the object on whose lock the block should synchronize.
(206) Which of the following are true? (Choose three.) | b. when an application begins running, there is one non-daemon thread,whose job is to execute main().c. a thread created by a daemon thread is initially also a daemon thread.d. a thread created by a non-daemon thread is initially also a non-daemon thread.
(207) Which of the following are true? (Choose one.) | d. the jvm runs until there are no non-daemon threads.
(250) Which of the following are true? (Choose one.) | e. all the above
(227) Which of the following are methods of the java.util.SortedSet interface? | f. all the above
(228) Which of the following are methods of the java.util.SortedMap interface?(Choose three.) | c. headmap d. tailmape. submap
(223) Which of the following are legal? (Choose two.) | b. list<string> thelist = new vector<string>();d. vector <string> thevec = new vector<string>();
(63) Which of the following are legal? (Choose two.) | a. char c = 0x1234;c. char c = '\u1234';
(61) Which of the following are legal? (Choose two.) | c. int c = 0xabcd;d. int d = 0xabcd;
(159) Which of the following are legal? (Choose three.) | a. for (int i=0, j=1; i<10; i++, j++)b. for (int i=0, j=1;; i++, j++)d. for (string s = ""; s.length()<10; s += '!')
(161) Which of the following are legal loop definitions? (Choose one.) | f. none of the above.
(149) Which of the following are legal loop constructions? (Choose one.) | c. int j = 0;for (int k=0, j+k != 10; j++,k++) { system.out.println("j=" + j + ", k=" + k);}
(57) Which of the following are legal import statements? (Choose two.) | a. import java.util.vector;c. import static java.util.vector.*;
(177) Which of the following are legal enums? (Choose three.) | a. enum animals { lion, tiger, bear }c. enum animals {lion, tiger, bear;int weight;}e. enum animals {lion(450), tiger(450), bear;int weight; animals() { } animals(int w) {weight = w; }}
(162) Which of the following are legal argument types for a switch statement?(Choose three.) | a. byteb. inte. char
(114) Which modifier or modifiers should be used to denote a variable thatshould not be written out as part of its class's persistent state? (Choose the shortest possible answer.) | d. transient
(189) Which methods return an enum constant's name? (Choose two.) | b. name()c. tostring()
(1411) Which Man class properly represents the relationship "Man has the bestfriend who is a Dog"? (Choose one.) | d. class man { private dog bestfriend; }
(229) Which line of code tells a scanner called sc to use a single digit as adelimiter? (Choose one.) | c. sc.usedelimiter("\\d");
(7256) Which JDBC processing model that requires a JDBC driver that can communicate with the particular data source beingaccessed? | a. two-tier
(4928) Which is the four steps are used in working with JDBC? | a. 1)connect to the database 2)create a statement and execute the query3)look at the result set4)close connection
(302) Which is four-step approach to help you organize your GUI thinking.(Choose one.) | a. identify needed components. isolate regions of behavior. sketch the gui.choose layout managers.
(1879) Which class and static method can you use t convert an array to a List? (Choose one.) | a. arrays.aslist
(313) Whenever a method does not want to handle exceptions using the try block, the is used. | a. throws
(312) When the user selects a menu item, event is generated. | b. action event
(308) When the user attempts to close the frame window, event ingenerated. | a. window closing
(166) When is it appropriate to write code that constructs and throws an error? (Choose one.) | e. never
(165) When does an exception's stack trace get recorded in the exception object? (Choose one.) | a. when the exception is constructed
(1531) When comparing java.io.BufferedWriter to java.io.FileWriter, whichcapability exists as a method in only one of the two? (Choose one.) | e. writing a line separator to the stream
(143) When a negative long is cast to a byte, what are the possible values of the result? (Choose one.) | d. all the above
(144) When a negative byte is cast to a long, what are the possible values of the result? (Choose one.) | c. negative
(78) When a byte is added to a char, what is the type of the result? | c. int
(150) What would be the output from this code fragment?1. int x = 0, y = 4, z = 5;2. if (x > 2) {3. if (y < 5) {4.System.out.println("message one");5. }6. else {7. System.out.println("message two");8. }9. }10. else if (z > 5) {11. System.out.println("message three");12. }13. else {14. System.out.println("message four");15. } | d. message four
(73) What results from running the following code?1. public class Xor {2. public static void main(String args[]) {3. byte b = 10; // 00001010 binary4. byte c = 15; // 00001111 binary5. b = (byte)(b ^ c);6. System.out.println("b contains " + b);7. }8. } | b. the output: b contains 5
(74) What results from attempting to compile and run the following code?1. public class Conditional {2. public static void main(String args[]) {3. int x = 4;4. System.out.println("value is " + ((x > 4) ? 99.99 : 9));5. }6. } | c. the output: value is 9.0
(249) What method of the java.io.File class can create a file on the hard drive? | e. createnewfile()
What is the return type of the instance of operator? | d. a boolean
(242) What is the result of attempting to compile and execute the following code fragment? Assume that the code fragment is part of an application that has write permission in the current working directory. Also assume that before execution, the current working directory does not contain a file called datafile. (Choose one.)1. try {2. RandomAccessFile raf = new3. RandomAccessFile("datafile" ,"rw");4.BufferedOutputStream bos = newBufferedOutputStream(raf);5.6. DataOutputStream dos = new DataOutputStream(bos);7.8. dos.writeDouble(Math.PI);9. dos.close();10. bos.close();11. raf.close();12. }13. catch (IOException e) { } | a. the code fails to compile.
(53) What is the range of values that can be assigned to a variable of type short?(Choose one.) | d. -2^15 through 2^15 - 1
(54) What is the range of values that can be assigned to a variable of type byte? (Choose one.) | d. -2^7 through 2^7 - 1
What is the minimal modification that will make this code compile correctly? (Choose one.)1. final class Aaa2. {3. int xxx;4. void yyy() { xxx = 1; }5. }6.7.8. class Bbb extends Aaa9. {10. final Aaa finalref = new Aaa();11.12. final void yyy()13. {14. System.out.println("In methodyyy()");15. finalref.xxx= 12345;16. }17. } | a. on line 1, remove the final modifier.
(146) What is the difference between the rules for method-call conversion andthe rules for assignment conversion? (Choose one.) | a. there is no difference; the rules are the same.
(86) What is -50 >> 2 | c. -13
What happens when you try to compile and run this application? (Choose one.)1. import java.util.*;2.3. public class Apple {4. public static void main(String[] a) {5. Set<Apple> set = new TreeSet<Apple>();6. set.add(new Apple());7. set.add(new Apple());8. set.add(new Apple());9. }10. } | c. an exception is thrown at line 7.
(59) What happens when you try to compile and run the following code?public class Q {static String s;public static void main(String[] args) {System.out.println(">>" + s + "<<");}} | b. the code compiles, and prints out >><<
A that2 = new A();that1.x = 5; that2.x = 1000; x = -1;System.out.println(x);}} | d. -1
(238) What does the following code fragment print out at line 9? (Choose one.)1. FileOutputStream fos = new FileOutputStream("xx");2. for (byte b=10; b<50; b++)3. fos.write(b);4. fos.close();5. RandomAccessFile raf = new RandomAccessFile("xx", "r");6. raf.seek(10);7. int i = raf.read();8. raf.close()9. System.out.println("i = " + i); | b. the output is i = 20.
(75) What does the following code do? Integer i = null;if (i != null & i.intValue() == 5) System.out.println("Value is 5"); | b. throws an exception.
(4930) URL referring to databases use the form: | a. protocol:subprotocol:datasoursename
(191) This question involves IOException, AWTException, and EOFException.They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends OException.Suppose class X contains the following method:void doSomething() throws IOException{ ... }Which of the following methods may appear in class Y, which extends X? (Choose three.) | a. void dosomething() { ... }c. void dosomething() throws eofexception { ... }d. void dosomething() throws ioexception, eofexception { ... }
N=143 There are two classes in Java to enable communication using datagrams(310) namely. | a. datapacket and datasocket
short s = 10;whatsMyType = !s; | c. there are no possible legal types.
Suppose a source file contains a large number of import statements. How do the imports affect the time required to compile the source file? | compilation takes slightly more time.
Which of the following is legal import statement? | import java.util.vector.*.*;
What will happen if you try to compile and run the following code? public class Q { public static void main(String argv[]){ int anar[]=new int[5];System.out.println(anar[0]); }} | 0
Which of the following code snippets does not compile? | int i = 7; byte b = i;
Given the following class definition public class Upton{ public static void main(String argv[]){  public void amethod(int i){}//Here}Which of the following would be illegal to place after the comment //Here ? | public int amethod(int z){}
What will be printed out if this code is run with the following command line? java myprog good morning public class myprog{ public static void main(String argv[]) {System.out.println(argv[2]); } | exception raised: "java.lang.arrayindexoutofboundsexception: 2"
Which of the following signatures is valid for the main() method entry point of an application? | public static void main(string arg[])
What is the output when the following program is run? class A {public int x;} public class Main  {static void fun(A t) {t.x += 2;} public static void main(String args[]) {A t = new A();  t.x = 99;System.out.print(t.x + "  "); t.x++;System.out.print(t.x + "  ");fun(t);System.out.println(t.x); | 99  100  102
Which of the following will compile without error (select two) | package mypackage;import java.awt.*;class myclass{}_ /*this is a comment */package mypackage;import java.awt.*;class myclass{}
Which of the following is an example of a bool-expression? | cause == byes
You want to find out the value of the last element of an array. You write the following code. What will happen when you compile and run it.? public class MyAr{ public static void main(String argv[]){int[] i = new int[5];System.out.println(i[5]);} | an error at run time
In the following code, what are the possible types for variable result? (Select the most correct answer) 1. byte b = 11;2. short s = 13;3. result = b * ++s; | int, long, float, double
What is the return type of the instanceof operator? | an boolean
Which of the following statements is true? | object references can be converted in both method calls and assignments, and the rules governing these conversions are identical.
Which of the following statements is true? | a class that has one abstract method must be abstract class
Which one line in the following code will not compile? 1. byte b = 5;2. char c = ‘5’;3. short s = 55;4. int i = 555;5. float f = 555.5f;6. b = s;7. i = c;8. if (f > b)9.  f = i; | line 6
We can access a static variable through the class name? | true
Which one statement is true concerning the following code? 1. class Greebo extends java.util.Vector implements Runnable {3.  public void run(String message) {System.out.println("in run() method: " +  message);class GreeboTest {public static void main(String args[]) {Greebo g = new Greebo();Thread t = new Thread(g);t.start(); | there will be a compiler error, because class greebo does not correctly implement the runnable interface.
Which of the following may not be synchronized? | classes
What is the difference between yielding and sleeping? | when a task invokes its yield() method, it returns to the ready state. when a task invokes its sleep() method, it returns to the waiting state.
What will happen when you attempt to compile and run the following code? public class Tux extends Thread{static String sName = "ABC";public static void main(String argv[]){Tux t = new Tux(); t.piggy(sName);System.out.println(sName);public void piggy(String sName){sName = sName + " DE";start();public void run(){for(int i=0;i  <  4; i++){sName = sName + " " + i; | compilation and output of either "abc", "abc 0", "abc 0 1" "abc 0 1 2" or "abc 0 1 2 3"
When you call start() method of a thread, the code inside method run() will run immediately | false
Which is the last step of  four-step approach to help you organize your GUI thinking? | choose layout managers.
Select correct statement(s). (Select one option) (1) Swing is part of the Java Foundation Classes and provides a rich set of GUI components. (2) Before you think about what your GUI will look like, it’s important to think about what it will. | 1,2
Consider the following code developed in NetBeans. What does the thread  t  do? | it will show a clock in the jlabel1
Which of the following is NOT a swing component? | jtext
What results from running the following code?public class Xor {public static void main(String args[]) {byte b = 10; // 00001010 binarybyte c = 15; // 00001111 binaryb = (byte)(b ^ c);System.out.println("b contains " + b); | the output: b contains 5
After execution of the following code fragment, what are the values of the variables x, a, and b? 1. int x, a = 6, b = 7;2. x = a++ + b++; | x = 13, a = 7, b = 8
Which statement is true about the following method? int selfXor(int i) {return i ^ i; | it always returns 0.
After execution of the following code fragment, what are the values of the variables x, a, and b? int x, a = 6, b = 7; x = a++ + b++; | x = 13, a = 7, b = 8
Which of the following statements is true? | an abstract class may be inherited.
Study the statements:1)When a JDBC connection is created, it is in auto-commit mode2)Once auto-commit mode is disabled, no SQL statements will be committed until you call the method commit explicitly | both 1 and 2 are true
Select the most correct statement: | if a checked exception may be thrown within the body of a method, the method must either catch the exception or declare it in its throws clause.
What will be output when the following code is run without throwing Exception? class Test {public int foo(int x)    {int count=1; try { count += x; fun(count); count++; } catch(Exception e) { count -= x; } return(count); public void fun(int k){k++;class Main{public static void main(String [] args){Test t = new Test();System.out.println(t.foo(2)); | 4
Suppose salaries is an array containing floats. Which of the following are valid loop control statements for processing each element of salaries? | for (float f:salaries)
All of the numeric wrapper  classes in the java.lang package are subclasses of the abstract class ……. | java.lang.number
Which of the following is invalid wrapper class | java.lang.int
Which one statement is true about the following code? 1. String s1 = "abc" + "def";2. String s2 = new String(s1);4. System.out.println("== succeeded");6.      System.out.println(".equals() succeeded"); | line 6 executes and line 4 does not.
What happens when you try to compile and run the following program? import java.util.*;public class Main{TreeSet<Integer> t = new TreeSet<Integer>();t.add(12);t.add(2);Iterator<Integer> i = t.iterator();int sum=0;while(i.hasNext()) sum += i.next();System.out.println(sum); | the program will print out: 18
What happens when you try to compile and run this application? Object [] myObjects = { 24. 		new Integer(12), new String(”foo”), new Integer(5), new Boolean(true) 29. java.util.Array.sort(myObjects); 30. for( int i=0; i<myObjects.length; i++) { System.out.print(myObjects[i].toString()); System.out.print(” “); | compilation fails due to an error in line 29.
In order for objects in a List to be sorted, those objects must implement which interface and method? | comparable interface and its compareto method.
See picture: | gridbaglayout
One way to approach the daunting number of Swing components is to divide them into three categories:Container components Ordinary components Menu components | true
Consider the following definition:1. public class Outer {2.      public int a = 1;3.      private int b = 2;4.      public void oMethod() {int c = 3; final int d  = 4;.           class Inner {private void iMethod(int e) {}} Which line contain only variables, which can be referenced at line 8? | a, b, d, e
Which of the following may override a method whose signature is void xyz(float f)? | public void xyz(float f)
Which of the following is true? | an enum definition may contain the main() method of an application.
Which of the following is VALID? | vector <string> thevec = new vector<string>();
A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example, it may be called in these ways: logIt(”log message 1 “); logIt(”log message2”,”log message3”); logIt(”log message4”, “log message5”, “log message6“); | public void logit(string... msgs)
Consider the following class definition:1. public class Test extends Base {2.  public Test(int j) { public Test(int j, int k) { super(j, k);Which of the following are legitimate calls to construct instances of the Test class? (Select two) | test t = new test(1); test t = new test(1, 2);
Which of the following statement about inner class is true? | an anonymous inner class may implement at most one interface.
Which of the following class implement java.util.List? | java.util.arraylist
Consider these classes, defined in separate source files:1. public class Test1 {public float aMethod(float a, float b)  throws IOException {.. }1. public class Test2 extends Test1 {Which of the following methods would be legal (individually) at line 2 in class Test2? (Choose two) | public int amethod(int a, int b) throws exception {...}_ public float amethod(float p, float q) {...}
Is the following code valid? 1. public class Test1 {final void aMethod() {.. }public class Test2 extends Test1 {void aMethod() {.. } | no
Given: 10. class Main {11.   static class A { 12.     void process() throws Exception {  throw new Exception(); } 13.    } 14.   static class B extends A { void process() { System.out.println("B ");  }16.    } public static void main(String[] args) { A a=new B(); .       a.process(); What is the result when the above code is run? | compilation fails because of an error in line 19.
Is the following code valid? public class Test1 {public static void main(String[] args) {final int a = 5;  a = 10; } | no
Which of the following statements are true? (select two) | an inner class may be defined as static _ an inner class may extend another class
Is the following code valid?1. public abstract class Test1 {2.      abstract void aMethod();4. public class Test2 extends Test1 { } | no
Consider the following class definition: . public class Test extends Base { public Test(int j, int k) { super(j, k);}Which of the following form of constructor must exist explicitly in the definition of the Base class? Assume Test and Base are in the same package. | base(int j, int k) { }
(1) The java.io…. class makes it easier to write platform-independent code that examines and manipulates files.(2) The java.io.…. class makes it easier to write platform-independent code that examines and manipulates folders. | file, file
Which of the following methods of the java.io.File can be used to create a new file? | createnewfile()
Select INCORRECT statement about ServerSocket class. | to make the new object available for client connections, call its accept() method, which returns an instance of  serversocket
Which of the following statements are true? (Select two) | tcp provides a point-to-point channel for applications that require reliable connections._udp is a protocol that sends independent packets of data, called datagrams, from one computer to  another with no guarantee about arrival.
1.TCP is a connection-based protocol that provides a reliable flow of data between two computers.2.TCP provides point-to-point channel for applications that require reliable communications: | both 1 and 2 are true
Which of the following statements is INCORRECT? | all methods in an abstract class must be declared as abstract
An abstract class ……… | can contain all concrete methods.
1.Which of the following are valid declarations? Assume java.util.* is imported. | vector<map>   v;set<string> s;	map<string, string>  m;
2.You can determine  all the keys in a Map in which of the following ways? | by getting a set object from the map and iterating  through it.
Select the order of access modifiers from least restrictive to most restrictive. | public, protected, default,  private
Given the following code, what will be the outcome?public class Funcs   extends java.lang.Math  { public int  add(int x, int  y) {return x  + y;public int  sub(int x, int  y) { return x  - y;public static  void main(String []  a) { Funcs   f = new Funcs(); System.out.println("" + f.add(1, 2)); | the code does not compile.
Given the following code, what is the expected outcome?public  class  Test {public static  void main(String []  a) { int [] b  = [1,2,3,4,5,6,7,8,9,0]; System.out.println("a[2]=" + a[2]); | the code does not compile.
What is the value of x after the following operation is performed?x  = 23  %   4; | 3
Given the following code, what keyword  must be used at line 4 in order to stop execution of the for loop? 1.	boolean b  = true;2.	for (;;) {3.	if (b)  {4.	<insert code>6.	// do  something | break
Given the following code, which of the results that follow would you expect?.  package mail; 2.3.	interface Box {4.	protected  void open();5.	void close();6.	public  void empty(); | the code will not compile because of line 4.
Select the valid primitive data types. (Select all that apply.) | boolean_ c.	chard.	float
What is the value of x after the following line is executed?x  = 32  *  (31   - 10  *  3); | 32
StringBuffer is slower than a StringBuilder, but a StringBuffer is threadsafe. | true
22.	Select the list of primitives ordered  in smallest to largest bit size representation. | char, int, float, long
23.	Which class provides locale-sensitive text formatting for date and time information? | java.text.dateformat
24.	The following line of code is valid.int x  = 9; byte b  = x; | false
14.	Which of the following code snippets compile? | integer i =  7;b.	integer i =  new integer(5); int j =  i;c.	byte b  =  7;
26.	What will be the output of the following code?public class  StringTest {public static  void main(String []  a) { String s1  = "test string";String s2  = "test string"; if (s1 == s2)  {System.out.println("same");}  else  { System.out.println("different"); | “same” will be printed  out to the console.
27.	Java arrays always start at index 1. | false
29.	How  do you change the value that  is encapsulated by a wrapper class after you have instan- tiated it? | none of the above.
30.	Suppose you are writing a class that provides custom deserialization. The class implements java.io.Serializable (and not java.io.Externalizable). What method  should imple- ment the custom deserialization, and what is its access mode? | private  readobject
1.	A signed data type has an equal number  of non-zero  positive and negative values available. | false
2.	Choose the valid identifiers from those listed here. (Choose all that apply.) | bigollongstringwithmeaninglessname_ b.	$int_c.	bytes_d.$1e.	finalist
3.	Which of the following signatures are valid for the main() method entry point of an application?(Choose all that apply.) | public static  void main(string arg[])d.public static  void main(string[] args)
4.	If all three top-level elements occur in a source file, they must appear  in which order? | package declaration, imports,  class/interface/enum definitions.
5.	Consider  the following line of code: int[] x  = new int[25]; | x[24] is 0 e.	x.length is 25
6.	Consider  the following application:1.	class Q6 {2.	public static  void main(String args[])  {3.	Holder h  = new Holder();4.	h.held = 100;5.	h.bump(h);6.	System.out.println(h.held);10.	class  Holder {11.	public int held;12.	public  void bump(Holder theHolder)  {13.	theHolder.held++;  } | 101
7.	Consider  the following application:1.	class Q7 {2.	public static  void main(String args[])  {3.	double d  = 12.3;4.	Decrementer dec  = new Decrementer();5.	dec.decrement(d);6.	System.out.println(d);10.	class Decrementer  { 11.	public  void decrement(double decMe)  {12.	decMe = decMe - 1.0;What value is printed  out at line 6? | 12.3
8.	How can you force garbage collection of an object? | garbage  collection cannot  be forced.
9.	What is the range of values that can be assigned to a variable of type short? | -215  through 215   - 1
11.	Suppose a source file contains a large number  of import statements. How do the imports  affect the time required  to compile the source file? | compilation takes slightly more time.
12.	Suppose a source file contains  a large number  of import statements  and one class definition.How do the imports  affect the time required  to load the class? | class loading takes no additional time.
13.	Which of the following are legal import statements? | import  java.util.vector;c.	import  static java.util.vector.*;
14.	Which of the following may be statically imported? (Choose all that apply.) | static method  namesc.	static field names
15.	What happens  when you try to compile and run the following code?public class Q15 { static  String s;public static  void main(String[]  args)  {System.out.println(“>>” + s + “<<”); | the code compiles, and prints out >>null<<
16.	Which of the following are legal? (Choose all that apply.) | int c  =  0xabcd;d.	int d  =  0xabcd;
17.	Which of the following are legal? (Choose all that apply.) | double d  =  1.2d;b.	double d  =  1.2d;
18.	Which of the following are legal? | char c  =  ‘\u1234’;
19.	Consider  the following code:1.	StringBuffer  sbuf = new StringBuffer();2.	sbuf = null;3.	System.gc();Choose all true statements: | after line 2 executes, the stringbuffer object is eligible for garbage collection.
20.	Which of the following are true? (Choose all that apply.) | primitives are passed by value.d.	references are passed by value.
1.	After execution  of the following code fragment,  what are the values of the variables x, a, and b?1.	int x, a  = 6, b  = 7;2.	x  = a++  + b++; | x = 13, a = 7, b = 8
2.	Which of the following expressions  are legal? (Choose all that apply.) | int x  =  6; if (!(x >  3))  {}c.	int x  =  6; x  =  ~x;
3.	Which of the following expressions  results in a positive value in x? | int x  =  –1; x  =  x  >>> 5;
4.	Which of the following expressions  are legal? (Choose all that apply.) | string x  =  "hello"; int y  =  9; x  += y;c.	string x  =  "hello"; int y  =  9; x  =  x  +  y;
7.	What results from running  the following code? | 1.	public class xor  {2.	public static  void main(string args[])  {3.	byte b  = 10; // 00001010   binary1.	byte c  = 15; // 00001111   binary5.	b  = (byte)(b ^  c);6.	system.out.println("b contains " + b);  |   B.	The output: b  contains  5
8.	What results from attempting to compile and run the following code?1.	public class  Conditional {2.	public static  void main(String args[])  {3.	int x  = 4;4.	System.out.println("value is  " +5.	((x > 4) ?  99.99 : 9)); | the output: value  is 9.0
9.	What does the following code do?Integer i = null;if (i !=  null   &      i.intValue() == 5) System.out.println(“Value is  5”); | throws  an exception.
10.	Is it possible to define a class called Thing  so that the following method  can return  true under certain circumstances?boolean weird(Thing s)  { Integer x  = new Integer(5); return s.equals(x); | yes
11.	Suppose ob1  and ob2  are references to instances of java.lang.Object. If (ob1 == ob2) is false, can ob1.equals(ob2) ever be true? | no
12.	When a byte is added to a char, what is the type of the result? | int
13.	When a short is added to a float, what is the type of the result? | float
14.	Which statement is true about  the following method?int selfXor(int i)  { return i ^  i; | it always returns  0.
15.	Which of the following operations might throw  an ArithmeticException? | none of these
16.	Which of the following operations might throw  an ArithmeticException? | /
17.	What is the return  type of the instanceof operator? | a boolean
18.	Which of the following may appear  on the left-hand  side of an instanceof operator? | a reference
19.	Which of the following may appear on the right-hand side of an instanceof operator? (Choose all that apply.) | a classc.	an interface
20.	What is -50  >>  1? | -25
1.	Which of the following declarations are illegal? (Choose all that apply.) | default string s;d.	abstract  double d;e.	abstract  final  double hyperboliccosine();
2.	Which of the following statements  is true? | a final class may not have any abstract methods.
3.	What is the minimal modification that will make this code compile correctly?1.	final class Aaa3.	int xxx;8.	class Bbb extends Aaa10.	final Aaa  finalref =  new  Aaa(); 11.14.	System.out.println("In method  yyy()");15.	finalref.xxx = 12345; | on line 1, remove the final modifier.
4.	Which of the following statements  is true? | transient variables are not serialized.
5.	Which statement is true about  this application?. class StaticStuffstatic int x  = 10; 4.5.	static {  x  += 5; } 6.7.	public static  void main(String args[])9.	System.out.println("x = " + x);12.	static {x  /= 5; } | the code compiles and execution  produces  the output x = 3.
6.	Which statement is true about  this code?1.	class HasStatic3.	private static int x  = 100; 4.7.	HasStatic hs1  = new HasStatic();9.	HasStatic hs2  = new HasStatic();hs1  = new HasStatic();System.out.println("x = " + x); | the program compiles and the output is x = 104.
7.	Given the following code, and making no other changes, which combination of access modifiers (public, protected, or private) can legally be placed before aMethod() on line 3 and be placed before aMethod() on line 8? | 1.	class superduper3.	void  amethod() {  }6.	class sub  extends superduper8.	void  amethod() {  }  |   D.	line 3: private; line 8: protected
8.	Which modifier or modifiers should be used to denote a variable that should not be written out as part of its class’s persistent  state? (Choose the shortest  possible answer.) | transient
9.	This question  concerns the following class definition:package abcde; 2.4.	protected static  int referenceCount = 0;6.	protected void fly()  {  /* Flap wings, etc.  */ }7.	static int getRefCount() {  return  referenceCount; }Which statement is true about  class Bird and the following class Parrot?3.	class  Parrot  extends abcde.Bird {4.	public void fly()  {5.	/* Parrot-specific flight  code. */7.	public int  getRefCount() {8.	return referenceCount; | compilation of parrot.java fails at line 7 because method  getrefcount() is static in the superclass, and static methods  may not be overridden to be nonstatic.
This question  concerns the following class definition: 3.	public  class  Bird {4.	protected static  int referenceCount = 0;5.	public Bird() {  referenceCount++;  }6.	protected void fly()  {  /* Flap wings, etc.  */ }7.	static int getRefCount() {  return  referenceCount; }Which statement is true about  class Bird and the following class Nightingale? 3.	class  Nightingale extends abcde.Bird {6.	public static  void main(String args[])  {7.	System.out.print("Before: " + referenceCount);8.	Nightingale florence = new Nightingale();9.	System.out.println("   After: " + referenceCount);10.	florence.fly(); | the program will compile and execute. the output will be before: 0    after: 2.
11.	Suppose class Supe, in package packagea, has a method called doSomething(). Suppose class Subby, in package packageb, overrides  doSomething(). What  access modes may Subby’s version of the method  have? (Choose all that  apply.) | publicb.	protected
12.	Which of the following statements  are true? | f.	none of the above.
13.	Suppose interface Inty defines five methods.  Suppose class Classy declares that it implementsInty but does not provide implementations for any of the five interface methods. Which is/are true? | the class will compile if it is declared abstract.d.	the class may not be instantiated.
14.	Which of the following may be declared final? (Choose all that apply.) | classesb.	datac.	methods
15.	Which of the following may follow the static keyword?  (Choose all that apply.) | datac.	methodsd.	code blocks enclosed in curly brackets
16.	Suppose class A has a method  called doSomething(), with default access. Suppose class B extends A and overrides  doSomething(). Which access modes may apply to B’s version of doSomething()? (Choose all that apply.) | public c.	protected d.	default
17.	True or false: If class Y extends class X, the two classes are in different packages, and class X has a protected  method  called abby(), then any instance of Y may call the abby() method  of any other instance of Y. | false
18.	Which of the following statements  are true? | a final class may not be extended.
20.	What does the following code print?public class Astatic int x;public static  void main(String[]  args)  { A  that1 = new A  that2 = new A(); that1.x = 5; x  = -1; System.out.println(x); | -1
4.	In the following code, what are the possible types for variable result? (Choose the most complete true answer.) 1.	byte b  = 11;2.	short s = 13;3.	result = b  *  ++s; | int, long, float, double
5.	Consider  the following class:1.	class  Cruncher {2.	void crunch(int  i) {3.	System.out.println("int version");6.	System.out.println("String version");10.	Cruncher crun = new Cruncher();11.	char ch  = ‘p’;12.	crun.crunch(ch); | the code will compile and produce  the following output: int version.
7.	Consider  the following code. Which line will not compile? 1.	Object ob  = new Object();2.	String[] stringarr = new String[50];3.	Float floater  = new Float(3.14f);5.	ob  = stringarr[5];7.	ob  = floater; | line 6
8.	Consider  the following code: 	1.	Dog	rover, fido;2.	Animal	anim; 3.4.	rover = new Dog();6.	fido = (Dog)anim;Which of the following statements  is true? (Choose one.) | the code will compile and run.
9.	Consider  the following code: 1.	Cat  sunflower;5.	sunflower = new Cat();7.	pogo  = (SwampThing)wawa; | the code will compile but will throw  an exception  at line 7, because the runtime  class of wawa cannot  be converted  to type swampthing.
10.	Consider  the following code: 2.	SwampThing pogo;5.	rocky = new Raccoon();6.	w  = rocky;7.	pogo  = w;Which of the following statements  is true? (Choose one.) | line 7 will not compile; an explicit cast is required  to convert a washer to a swampthing.
11.	Which of the following may legally appear  as the new type (between the parentheses)  in a cast operation? | all of the above
12.	Which of the following may legally appear  as the new type (between the parentheses)  in a cast operation? | all of the above
13.	Suppose the declared type of x is a class, and the declared type of y is an interface. When is the assignment  x  =  y; legal? | when the type of x is object
14.	Suppose the type of xarr is an array of XXX, and the type of yarr is an array of YYY. When is the assignment  xarr =  yarr; legal? | sometimes
15.	When is x  &   y an int? (Choose one). | sometimes
16.	What are the legal types for whatsMyType? short s = 10; whatsMyType  = !s; | there are no possible legal types.
17.	When a negative long is cast to a byte, what are the possible values of the result? | all of the above
18.	When a negative byte is cast to a long, what are the possible values of the result? | negative
19.	Which of the following operators can perform  promotion on their operands? (Choose all that  apply.) | .  +b.  -e.	~
20.	What is the difference between the rules for method-call conversion and the rules for assignment conversion? | there is no difference; the rules are the same.
1.	Consider  the following code:1.	for (int i = 0; i < 2;  i++) {2.	for (int j = 0; j < 3;  j++) {3.	if (i == j) {4.	continue;6.	System.out.println("i = " + i + " j = " + j);Which lines would be part of the output? (Choose all that apply.) | i =  0  j =  1c.	i =  0  j =  2d.	i =  1  j =  0f.	i =  1  j =  2
2.	Consider  the following code:1.	outer: for (int i = 0; i < 2;  i++) {2.	for (int j = 0; j < 3;  j++) {3.	if (i == j) {6.	System.out.println("i = " + i + " j = " + j);Which lines would be part of the output? (Choose all that apply.) | i =  1  j =  0
3.	Which of the following are legal loop constructions? (Choose all that apply.) | int j =  0;for (int  k=0, j+k   !=  10;  j++,k++) { system.out.println("j=" +  j +  ", k="  +  k);}
4.	What would be the output from this code fragment?1.	int x  = 0, y  = 4, z  = 5;2.	if (x > 2) {3.	if (y < 5) {4.	System.out.println("message one");10.	else if (z > 5) {11.	System.out.println("message three");14.	System.out.println("message four"); | message four
5.	Which statement is true about  the following code fragment?1.	int j = 2;2.	switch (j) {4.	System.out.println("value is  two");5.	case 2  + 1:6.	System.out.println("value is  three");8.	default:9.	System.out.println("value is  " + j); | the output would be the text value is two followed by the text value is three.
6.	Consider  the following class hierarchy  and code fragment:3.	URL  u  = new URL(s);4.	// in is an  ObjectInputStream6.	System.out.println("Success");9.	System.out.println("Bad URL");11.	catch  (StreamCorruptedException e)  {12.	System.out.println("Bad file contents");18.	System.out.println("Doing finally part");What lines are output if the constructor at line 3 throws  a MalformedURLException? (Choose all that apply.) | bad  urle.	doing  finally partf.	carrying  on
7.	Consider  the following class hierarchy  and code fragment:3.	URL  u  = new URL(s); 5.	Object o  = in.readObject();8.	catch (MalformedURLException e) {12.	System.out.println("Bad file contents");14.	catch (Exception e)  {15.	System.out.println("General exception");18.	System.out.println("Doing finally part");What lines are output if the methods at lines 3 and 5 complete successfully without throwing any exceptions?  (Choose all that apply.) | successe.	doing  finally partf.	carrying  on
2.	// assume   s is  previously defined4.	// in is an  ObjectInputStream6.	System.out.println("Success");11.	catch  (StreamCorruptedException e)  {15.	System.out.println("General exception");18.	System.out.println("Doing finally part");20.	System.out.println("Carrying on");What lines are output if the methods at lines 3 and 5 complete successfully without throwing any exceptions?  (Choose all that apply.) | success e.	doing  finally partf.	carrying  on
4.	// in is an  ObjectInputStream5.	Object o  = in.readObject();8.	catch (MalformedURLException e) {9.	System.out.println("Bad URL");11.	catch  (StreamCorruptedException e)  {12.	System.out.println("Bad file contents");15.	System.out.println("General exception");18.	System.out.println("Doing finally part");What lines are output if the method at line 5 throws an OutOfMemoryError? (Choose all that apply.) | doing  finally part
9.	Which of the following are appropriate situations for assertions? | postconditions of a public methodc.	preconditions of a private methodd.	postconditions of a private method
10.	Consider  the following code:1.	public class Assertification  {2.	public static  void main(String[]  args)  {3.	assert args.length == 0;Which of the following conditions must be true in order for the code to throw an AssertionError?Assume you are using release 5.0. (Choose all that apply.) | the source code must be compiled with the -source  1.5 flag.b.	the application must be run with the -enableassertions flag or another assertion- enabling flag.d.	the args array must have one or more elements.
11.	Which of the following is the most appropriate way to handle invalid arguments  in a public method? | throw  java.lang.illegalargumentexception.
12.	Suppose salaries is an array containing  floats. Which of the following are valid loop control statements  for processing each element of salaries? | for (float f:salaries)
13.	Which of the following are legal? (Choose all that apply.) | for (int  i=0, j=1; i<10; i++, j++) b.	for (int  i=0, j=1;; i++, j++)d.	for (string s =  “”; s.length()<10; s += ‘!’)
14.	Suppose a method  called finallyTest() consists of a try block, followed by a catch block, followed by a finally block. Assuming the JVM doesn’t crash and the code does not execute a System.exit() call, under what circumstances  will the finally block not begin to execute? | if the jvm doesn’t crash and the code does not execute a system.exit() call, the finally block will always execute.
15.	Which of the following are legal loop definitions?  (Choose all that apply.) | f.	none of them are legal.
16.	Which of the following are legal argument types for a switch statement? | byteb.	inte.	char
17.	When is it appropriate to pass a cause to an exception’s constructor? | when the exception  is being thrown in response to catching of a different exception  type
18.	Which of the following should always be caught? | checked exceptions
19.	When does an exception’s stack trace get recorded  in the exception  object? | when the exception  is constructed
20.	When is it appropriate to write code that constructs and throws  an error? | never
1.	Consider  this class:1.	public  class  Test1 {2.	public float aMethod(float a, float  b) {3.	} 4.Which of the following methods  would be legal if added (individually)  at line 4? (Choose all that  apply.) | public int  amethod(int a,  int  b) {  }c.	public float  amethod(float a, float b, int c) throws exception {  }e.	private float amethod(int a,  int  b,  int  c)  {  }
2.	Consider  these classes, defined in separate  source files:2.	public float aMethod(float a, float b)3.	throws IOException {...public class  Test2 extends Test1 { 2.Which of the following methods  would be legal (individually)  at line 2 in class Test2? (Choose all that apply.) | public int  amethod(int a,  int  b) throws exception {...} 	d.	public float  amethod(float p, float q) {...}
4.	You have been given a design document for a veterinary registration system for implementation in Java. It states:A pet has an owner,  a registration date, and a vaccination-due date. A cat is a pet that has a flag indicating if it has been neutered,  and a textual  description  of its markingsGiven that the Pet class has already been defined and you expect the Cat class to be used freely throughout the application, how would you make the opening declaration of the Cat class, up to but not including the first opening brace? Use only these words and spaces: boolean, Cat, class, Date,  extends, Object, Owner, Pet, private, protected, public, String | public class cat   extends pet
5.	Consider  the following classes, declared in separate  source files1.	public class Base  2.	public  void method(int i) {3.	System.out.print(“Value is  “  + i);2.	public  void method(int j) {6.	System.out.print(“I was  passed “  + s);8.	public static  void main(String args[])  {9.	Base  b1  = new Base();11.	b1.method(5);12.	b2.method(6);What output results when the main method  of the class Sub is run? | value   is  5this value is  6
6.	Consider  the following class definition:1.	public class  Test extends Base  {2.	public Test(int j) {4.	public Test(int  j, int  k) {5.	super(j, k);Which of the following are legitimate calls to construct instances of the Test class? (Choose all that apply.) | test t =  new test(1);c.	test t =  new test(1, 2);
7.	Consider  the following class definition:1.	public class  Test extends Base  {2.	public Test(int j) {4.	public Test(int  j, int  k) {5.	super(j, k);Which of the following forms of constructor must exist explicitly in the definition  of the Base class? Assume Test and Base are in the same package.  (Choose all that apply.) | base() {  }c.	base(int j, int k) {  }
8.	Consider  the following definition:1.	public  class  Outer {3.	private int b  = 2;4.	public void method(final int  c) {5.	int d  = 3;7.	private void  iMethod(int e) { 8.Which variables can be referenced at line 8? (Choose all that apply.) | a b.	b c.	c e.	e
9.	Which of the following statements  are true? (Choose all that apply.) | given that inner is a nonstatic class declared inside a public class outer and that appro- priate constructor forms are defined, an instance of inner can be constructed like this: new outer().new inner()
10.	Which of the following are legal enums? | enum animals {lion,  tiger,  bear; int weight;}e.	enum animals {lion(450),  tiger(450), bear; int weight;animals() {  } animals(int w)  {weight =  w;}
11.	Which of the following may override a method  whose signature  is void xyz(float  f)? | void xyz(float  f)b.	public void xyz(float  f)
12.	Which of the following are true? (Choose all that apply.) | an enum may contain  public method  definitions.d.	an enum may contain  private data.
13.	Which of the following are true? (Choose all that apply.) | an enum definition  may contain  the main() method  of an application.b.	you can call an enum’s tostring() method.c.	you can call an enum’s wait() method.d.	you can call an enum’s notify() method.
14.	Suppose x and y are of type TrafficLightState, which is an enum. What is the best way to test whether  x and y refer to the same constant? | if (x == y)
15.	Which of the following restrictions apply to anonymous inner classes? | they must be defined inside a code block.
16.	Given the following code, which of the following will compile?enum Spice {  NUTMEG,  CINNAMON,  CORIANDER,   ROSEMARY;  } | spice sp  =  spice.nutmeg; object ob  =  sp;b.	spice sp  =  spice.nutmeg; object ob  =  (object)sp;d.	object ob  =  new object();  spice sp  =  (spice)object;
17.	Which of the following are true? | an anonymous inner class may implement  at most one interface.c.	an anonymous inner class may extend a parent  class other than object.
18.	Which methods  return  an enum constant’s  name? | name()c.	tostring()
19.	Suppose class X contains  the following method:void doSomething(int a, float b)  {  …    }Which of the following methods  may appear  in class Y, which extends X? | public  void dosomething(int a, float b) {  …    }
20.	This question  involves IOException, AWTException, and EOFException. They are all checked exception types. IOException and AWTException extend Exception, and EOFException extends IOException. Suppose class X contains  the following method:void  doSomething() throws IOException{ …    }Which of the following methods  may appear  in class Y, which extends X? | void  dosomething() {  …    }c.	void  dosomething()  throws  eofexception {  …    }d.	void  dosomething() throws ioexception,  eofexception {  …    }
1.	Which one statement is true concerning  the following code?1.	class Greebo   extends java.util.Vector4.	System.out.println(“in run() method: “  +10.	public static  void main(String args[])  {13.	Thread t = new Thread(g);14.	t.start(); | there will be a compiler error,  because class greebo  does not correctly implement  the runnable interface.
2.	Which one statement is always true about  the following application?1.	class  HiPri extends Thread {3.	setPriority(10);7.	System.out.println(8.	“Another thread  starting up.”);9.	while (true)  {  }13.	HiPri hp1  = new HiPri();14.	HiPri hp2  = new HiPri();16.	hp1.start();18.	hp3.start(); | when the application is run, all three threads (hp1, hp2, and hp3) will execute concurrently, taking time-sliced turns in the cpu.
3.	A thread  wants to make a second thread  ineligible for execution.  To do this, the first thread  can call the yield() method  on the second thread. | false
4.	A thread’s run() method  includes the following lines:1.	try  {2.	sleep(100);catch (InterruptedException e) {  }Assuming the thread  is not interrupted, which one of the following statements  is correct? | at line 2, the thread will stop running. it will resume running some time after 100 milliseconds have elapsed.
5.	A monitor called mon has 10 threads in its waiting pool; all these waiting threads have the same priority.  One of the threads  is thr1. How can you notify thr1 so that it alone moves from the Waiting state to the Ready state? | 5.	a monitor called mon has 10 threads in its waiting pool; all these waiting threads have the same priority.  one of the threads  is thr1. how can you notify thr1 so that it alone moves from the waiting state to the ready state?
6.	If you attempt to compile and execute the following application, will it ever print  out the message In xxx?1.	class  TestThread3 extends Thread {3.	System.out.println(“Running”);4.	System.out.println(“Done”);8.	System.out.println(“In xxx”);12.	TestThread3 ttt = new TestThread3();14.	ttt.start(); | yes
8.	Which of the following methods  in the Thread class are deprecated? | suspend() and resume()
9.	Which of the following statements  about  threads  is true? | threads  inherit their priority  from their parent  thread.
10.	Which of the following statements  about  the wait() and notify() methods  is true? | the thread  that calls wait() goes into the monitor’s  pool of waiting threads.
11.	Which of the following may not be synchronized? | classes
12.	Which of the following calls may be made from a non-static synchronized method? | a call to the same method  of the current  object.b.	a call to the same method  of a different instance of the current  class.c.	a call to a different synchronized method  of the current  object.d.	a call to a static synchronized method  of the current  class.
13.	How many locks does an object have? | one
14.	Is it possible to write code that can execute only if the current  thread  owns multiple locks? | yes.
15.	Which of the following are true? (Choose all that apply.) | when an application begins running, there is one non-daemon thread, whose job is to execute main().c.	a thread  created by a daemon  thread  is initially also a daemon  thread.d.	a thread  created by a non-daemon thread  is initially also a non-daemon thread.
16.	Which of the following are true? | the jvm runs until there are no non-daemon threads.
17.	How do you prevent shared data from being corrupted in a multithreaded environment? | access the variables only via synchronized methods.
18.	How can you ensure that multithreaded code does not deadlock? | a, b, and c do not ensure that multithreaded code does not deadlock.
19.	Which of the following are true? (Choose all that apply.) | when you declare a method to be synchronized, the method always synchronizes on the lock of the current  objectd.	when you declare a block of code inside a method  to be synchronized, you can specify the object on whose lock the block should synchronize.
20.	Suppose you want to create a custom thread  class by extending  java.lang.Thread in order to provide some special functionality. Which of the following must you do? | override  run().
1.	Given a string constructed by calling s = new String(“xyzzy”), which of the calls modifies the string? | f.	none of the above
2.	Which one statement is true about  the following code? | line 6 executes and line 4 does not.
3.	Suppose you want to write a class that offers static methods to compute hyperbolic trigonometric functions.  You decide to subclass java.lang.Math and provide the new functionality as a set of static methods.  Which one statement is true about  this strategy? | the strategy fails because you cannot  subclass java.lang.math.
4.	Which one statement is true about  the following code fragment?1.	import java.lang.Math;3.	System.out.println(“cosine  of 0.123 = “  +4.	myMath.cos(0.123)); | compilation fails at line 2.
5.	Which one statement is true about  the following code fragment?2.	StringBuffer s1  = new StringBuffer(“abcde”);3.	if (s.equals(s1))4.	s1  = null;5.	if (s1.equals(s))6.	s = null; | compilation succeeds. no exception  is thrown during execution.
6.	In the following code fragment,  after execution  of line 1, sbuf references an instance of theStringBuffer class. After execution  of line 2, sbuf still references the same instance.1.	StringBuffer  sbuf = new StringBuffer(“abcde”);2.	sbuf.insert(3, “xyz”); | true
8.	In the following code fragment,  line 4 is executed.1.	String s1  = “xyz”;2.	String s2  = “xyz”;3.	if (s1 == s2)4.	System.out.println(“Line 4”); | true
9.	In the following code fragment,  line 4 is executed.1.	String s1  = “xyz”;2.	String s2  = new String(s1);3.	if (s1 == s2)4.	System.out.println(“Line 4”); | false
10.	Suppose prim  is an int and wrapped is an Integer. Which of the following are legal Java statements? (Choose all that  apply.) | prim   =  wrapped;b.	wrapped =  prim;c.	prim   =  new integer(9);d.	wrapped =  9;
11.	Which of the following are legal? (Choose all that apply.) | list<string> thelist  =  new vector<string>();d.	vector <string>  thevec =  new vector<string>();
12.	Given the following,Map<String> names  = new HashMap<String>();which of the following are legal? (Choose all that apply.) | iterator<string> iter =  names.iterator();b.	for (string s:names)
13.	Which of the following are legal clone() methods  in a class called Q13 that extends Object? | public object clone()throws clonenotsupportedexception {  return super.clone();  }d.	public q13 clone()throws clonenotsupportedexception {  return  (q13)super.clone();  }
14.	Which of the following classes implement  java.util.List? | java.util.arraylistd.	java.util.stack
15.	Which of the following are methods  of the java.util.SortedSet interface? | firstb.	lastc.	headsetd.	tailsete.	subset
16.	Which of the following are methods  of the java.util.SortedMap interface? | headmapd.	tailmape.	submap
17.	Which line of code tells a scanner called sc to use a single digit as a delimiter? | sc.usedelimiter(“\\d”);
18.	What happens  when you try to compile and run this application?1.	import  java.util.*; 2.4.	public static  void main(String[]  a)  {5.	Set<Apple> set = new TreeSet<Apple>();6.	set.add(new Apple());7.	set.add(new Apple()); | an exception  is thrown at line 7.
19.	Given arrays a1 and a2, which call returns  true if a1 and a2 have the same length, and a1[i].equals(a2[i]) for every legal index i? | java.util.arrays.equals(a1, a2);
20.	Which of the following statements  are true? | stringbuilder is generally faster than stringbuffer.d.	stringbuffer is threadsafe; stringbuilder is not.
1.	Which of the statements  below are true? (Choose all that apply.) | unicode characters are all 16 bits.
2.	Which of the statements  below are true? (Choose all that apply.) | none of the above.
3.	Which of the statements  below are true? (Choose all that apply.) | none of the above.
4.	How do you use the File class to list the contents  of a directory? | string[]  contents =  myfile.list();
5.	How many bytes does the following code write to file dest?2.	FileOutputStream fos = newFileOutputStream(“dest”);3.	DataOutputStream dos  = new DataOutputStream(fos);5.	dos.writeDouble(0.0001);7.	fos.close();9.	catch (IOException e) {  } | 12