Completed Task About Interfaces And Abstract Classes

Interfaces_And_Abstract_Classes/Interfaces_And_Abstract_Classes.iml

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+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

Interfaces_And_Abstract_Classes/src/BigDecimalOps.java

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+import java.math.BigDecimal;
+import java.math.RoundingMode;
+
+public final class BigDecimalOps {
+    private BigDecimalOps() {
+    }
+
+    public static double roundToNearestHundredth(BigDecimal value) {
+        if (value == null) throw new IllegalArgumentException("value cannot be null");
+        return value.setScale(2, RoundingMode.HALF_UP).doubleValue();
+    }
+
+    public static BigDecimal reverseSignAndRoundToNearestTenth(BigDecimal value) {
+        if (value == null) throw new IllegalArgumentException("value cannot be null");
+        return value.negate().setScale(1, RoundingMode.HALF_UP);
+    }
+}
+

Interfaces_And_Abstract_Classes/src/Car.java

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+public abstract class Car {
+    private final String vinNumber;
+    private final String make;
+    private final String model;
+    private int mileage;
+
+    protected Car(String vinNumber, String make, String model, int mileage) {
+        if (vinNumber == null || vinNumber.isBlank()) throw new IllegalArgumentException("vinNumber is required");
+        if (make == null || make.isBlank()) throw new IllegalArgumentException("make is required");
+        if (model == null || model.isBlank()) throw new IllegalArgumentException("model is required");
+        if (mileage < 0) throw new IllegalArgumentException("mileage cannot be negative");
+
+        this.vinNumber = vinNumber;
+        this.make = make;
+        this.model = model;
+        this.mileage = mileage;
+    }
+
+    public String getVinNumber() { return vinNumber; }
+    public String getMake() { return make; }
+    public String getModel() { return model; }
+    public int getMileage() { return mileage; }
+
+    public void setMileage(int mileage) {
+        if (mileage < 0) throw new IllegalArgumentException("mileage cannot be negative");
+        this.mileage = mileage;
+    }
+
+    public String getInfo() {
+        return String.format("VIN: %s | Make: %s | Model: %s | Mileage: %d",
+                vinNumber, make, model, mileage);
+    }
+}
+

Interfaces_And_Abstract_Classes/src/Inlist.java

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+public interface Inlist {
+    void add(int number);
+    int get(int id);
+}

Interfaces_And_Abstract_Classes/src/IntArrayList.java

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+public final class IntArrayList implements IntList {
+    private int[] data = new int[10];
+    private int size = 0;
+
+    @Override
+    public void add(int number) {
+        if (size == data.length) {
+            int newCap = data.length + (data.length / 2);
+            if (newCap == data.length) newCap = data.length + 1;
+            int[] newArr = new int[newCap];
+            System.arraycopy(data, 0, newArr, 0, data.length);
+            data = newArr;
+        }
+        data[size++] = number;
+    }
+
+    @Override
+    public int get(int id) {
+        if (id < 0 || id >= size) throw new IndexOutOfBoundsException("id: " + id + ", size: " + size);
+        return data[id];
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public int capacity() {
+        return data.length;
+    }
+}

Interfaces_And_Abstract_Classes/src/IntList.java

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+public interface IntList {
+    void add(int number);
+    int get(int id);
+}

Interfaces_And_Abstract_Classes/src/IntVector.java

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+public final class IntVector implements IntList {
+    private int[] data = new int[20];
+    private int size = 0;
+
+    @Override
+    public void add(int number) {
+        if (size == data.length) {
+            int newCap = data.length * 2;
+            int[] newArr = new int[newCap];
+            System.arraycopy(data, 0, newArr, 0, data.length);
+            data = newArr;
+        }
+        data[size++] = number;
+    }
+
+    @Override
+    public int get(int id) {
+        if (id < 0 || id >= size) throw new IndexOutOfBoundsException("id: " + id + ", size: " + size);
+        return data[id];
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public int capacity() {
+        return data.length;
+    }
+}

Interfaces_And_Abstract_Classes/src/Main.java

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+import java.math.BigDecimal;
+
+public class Main {
+    public static void main(String[] args) {
+
+        // ---- BigDecimal Operations ----
+        BigDecimal num1 = new BigDecimal("4.2545");
+        double res1 = BigDecimalOps.roundToNearestHundredth(num1);
+        System.out.println("4.2545 -> " + res1);
+
+        BigDecimal num2 = new BigDecimal("1.2345");
+        BigDecimal res2 = BigDecimalOps.reverseSignAndRoundToNearestTenth(num2);
+        System.out.println("1.2345 -> " + res2);
+
+        BigDecimal num3 = new BigDecimal("-45.67");
+        BigDecimal res3 = BigDecimalOps.reverseSignAndRoundToNearestTenth(num3);
+        System.out.println("-45.67 -> " + res3);
+
+        System.out.println("---------------");
+
+        // ---- Car Inventory System ----
+        Car c1 = new Sedan("VIN001", "Toyota", "Camry", 120000);
+        Car c2 = new UtilityVehicle("VIN002", "Jeep", "Wrangler", 80000, true);
+        Car c3 = new Truck("VIN003", "Ford", "F-150", 65000, 13500.5);
+
+        System.out.println("Cars:");
+        System.out.println(c1.getInfo());
+        System.out.println(c2.getInfo());
+        System.out.println(c3.getInfo());
+
+        System.out.println("---------------");
+
+        // ---- Video Streaming Service ----
+        Video v1 = new TvSeries("Breaking Bad", 49, 62);
+        Video v2 = new Movie("Interstellar", 169, 8.6);
+
+        System.out.println("Videos:");
+        System.out.println(v1.getInfo());
+        System.out.println(v2.getInfo());
+
+        System.out.println("---------------");
+
+        // ---- IntList ----
+        IntArrayList listA = new IntArrayList();
+        IntVector listB = new IntVector();
+
+        int i = 1;
+        while (i <= 25) {
+            listA.add(i);
+            listB.add(i);
+            i++;
+        }
+
+        System.out.println("IntArrayList values:");
+        System.out.println("first: " + listA.get(0));
+        System.out.println("middle: " + listA.get(12));
+        System.out.println("last: " + listA.get(24));
+        System.out.println("size: " + listA.size());
+        System.out.println("capacity: " + listA.capacity());
+
+        System.out.println();
+
+        System.out.println("IntVector values:");
+        System.out.println("first: " + listB.get(0));
+        System.out.println("middle: " + listB.get(12));
+        System.out.println("last: " + listB.get(24));
+        System.out.println("size: " + listB.size());
+        System.out.println("capacity: " + listB.capacity());
+    }
+}

Interfaces_And_Abstract_Classes/src/Movie.java

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+public final class Movie extends Video {
+    private final double rating;
+
+    public Movie(String title, int duration, double rating) {
+        super(title, duration);
+        if (rating < 0.0 || rating > 10.0) throw new IllegalArgumentException("rating must be between 0 and 10");
+        this.rating = rating;
+    }
+
+    public double getRating() {
+        return rating;
+    }
+
+    @Override
+    public String getInfo() {
+        return super.getInfo() + String.format(" | Rating: %.1f", rating);
+    }
+}

Interfaces_And_Abstract_Classes/src/Sedan.java

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+public final class Sedan extends Car {
+    public Sedan(String vinNumber, String make, String model, int mileage) {
+        super(vinNumber, make, model, mileage);
+    }
+}

Interfaces_And_Abstract_Classes/src/Truck.java

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+public final class Truck extends Car {
+    private final double towingCapacity;
+
+    public Truck(String vinNumber, String make, String model, int mileage, double towingCapacity) {
+        super(vinNumber, make, model, mileage);
+        if (towingCapacity < 0) throw new IllegalArgumentException("towingCapacity cannot be negative");
+        this.towingCapacity = towingCapacity;
+    }
+
+    public double getTowingCapacity() {
+        return towingCapacity;
+    }
+
+    @Override
+    public String getInfo() {
+        return super.getInfo() + String.format(" | Towing Capacity: %.1f", towingCapacity);
+    }
+}
+

Interfaces_And_Abstract_Classes/src/TvSeries.java

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+public final class TvSeries extends Video {
+    private final int episodes;
+
+    public TvSeries(String title, int duration, int episodes) {
+        super(title, duration);
+        if (episodes <= 0) throw new IllegalArgumentException("episodes must be positive");
+        this.episodes = episodes;
+    }
+
+    public int getEpisodes() {
+        return episodes;
+    }
+
+    @Override
+    public String getInfo() {
+        return super.getInfo() + String.format(" | Episodes: %d", episodes);
+    }
+}

Interfaces_And_Abstract_Classes/src/UtilityVehicle.java

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+public final class UtilityVehicle extends Car {
+    private final boolean fourWheelDrive;
+
+    public UtilityVehicle(String vinNumber, String make, String model, int mileage, boolean fourWheelDrive) {
+        super(vinNumber, make, model, mileage);
+        this.fourWheelDrive = fourWheelDrive;
+    }
+
+    public boolean isFourWheelDrive() {
+        return fourWheelDrive;
+    }
+
+    @Override
+    public String getInfo() {
+        return super.getInfo() + String.format(" | 4WD: %s", fourWheelDrive);
+    }
+}

Interfaces_And_Abstract_Classes/src/Video.java

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+public abstract class Video {
+    private final String title;
+    private final int duration;
+
+    protected Video(String title, int duration) {
+        if (title == null || title.isBlank()) throw new IllegalArgumentException("title is required");
+        if (duration <= 0) throw new IllegalArgumentException("duration must be positive");
+        this.title = title;
+        this.duration = duration;
+    }
+
+    public String getTitle() { return title; }
+    public int getDuration() { return duration; }
+
+    public String getInfo() {
+        return String.format("Title: %s | Duration: %d min", title, duration);
+    }
+}