Created MyCalculator and MyCalculatorTest class. Test coverage 100%

src/main/java/core/basesyntax/Calculator.java

@@ -0,0 +1,6 @@
+package core.basesyntax;
+
+public interface Calculator {
+
+    double calculate(double firstNumber, char operationType, double secondNumber);
+}

src/main/java/core/basesyntax/MyCalculator.java

@@ -0,0 +1,37 @@
+package core.basesyntax;
+
+public class MyCalculator implements Calculator {
+    private static final char ADDITION = '+';
+    private static final char SUBTRACTION = '-';
+    private static final char DIVISION = '/';
+    private static final char MULTIPLICATION = '*';
+    private static final char RAISING_TO_A_POWER = '^';
+
+    @Override
+    public double calculate(double firstNumber, char operationType, double secondNumber) {
+        switch (operationType) {
+            case ADDITION:
+                return checkResult(firstNumber + secondNumber);
+            case SUBTRACTION:
+                return checkResult(firstNumber - secondNumber);
+            case MULTIPLICATION:
+                return checkResult(firstNumber * secondNumber);
+            case DIVISION:
+                if (secondNumber == 0) {
+                    throw new OperationTypeException("You can't divide by zero");
+                }
+                return checkResult(firstNumber / secondNumber);
+            case RAISING_TO_A_POWER:
+                return checkResult(Math.pow(firstNumber, secondNumber));
+            default:
+                throw new OperationTypeException("This type of operation is not supported");
+        }
+    }
+
+    private double checkResult(double result) {
+        if (result == Double.POSITIVE_INFINITY || result == Double.NEGATIVE_INFINITY) {
+            throw new OperationTypeException("Too large or small value");
+        }
+        return result;
+    }
+}

src/main/java/core/basesyntax/OperationTypeException.java

@@ -0,0 +1,7 @@
+package core.basesyntax;
+
+public class OperationTypeException extends RuntimeException {
+    public OperationTypeException(String message) {
+        super(message);
+    }
+}

src/test/java/core/basesyntax/MyCalculatorTest.java

@@ -0,0 +1,274 @@
+package core.basesyntax;
+
+import static java.lang.Double.MAX_VALUE;
+import static java.lang.Double.MIN_VALUE;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+class MyCalculatorTest {
+    private static Calculator myCalculatorTest;
+    private static final double DELTA = 0.00001;
+    private static final char ADDITION = '+';
+    private static final char SUBTRACTION = '-';
+    private static final char MULTIPLICATION = '*';
+    private static final char DIVISION = '/';
+    private static final char RAISING_TO_A_POWER = '^';
+    private double actual;
+    private double expected;
+
+    @BeforeAll
+    static void beforeAll() {
+        myCalculatorTest = new MyCalculator();
+    }
+
+    @Test
+    void addition_PositiveNumbers_Ok() {
+        expected = 155.5;
+        actual = myCalculatorTest.calculate(90.5, ADDITION, 65.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void addition_NegativeNumbers_Ok() {
+        expected = -241.1;
+        actual = myCalculatorTest.calculate(-177.6, ADDITION, -63.5);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void addition_PositiveAndNegativeNumbers_Ok() {
+        expected = 136.5;
+        actual = myCalculatorTest.calculate(200.0, ADDITION, -63.5);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void addition_ZeroFirstNumberPosition_Ok() {
+        expected = -77;
+        actual = myCalculatorTest.calculate(0, ADDITION, -77.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void addition_ZeroSecondNumberPosition_Ok() {
+        expected = 200;
+        actual = myCalculatorTest.calculate(200.0, ADDITION, 0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void addition_MaxValues_NotOk() {
+        assertThrows(OperationTypeException.class, () ->
+                myCalculatorTest.calculate(MAX_VALUE, ADDITION, MAX_VALUE));
+    }
+
+    @Test
+    void addition_MinValues_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(MIN_VALUE, ADDITION, MIN_VALUE);
+        assertEquals(expected, actual, DELTA);
+    }
+
+    @Test
+    void subtraction_PositiveNumbers_Ok() {
+        expected = 25.5;
+        actual = myCalculatorTest.calculate(90.5, SUBTRACTION, 65.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_NegativeNumbers_Ok() {
+        expected = -114.1;
+        actual = myCalculatorTest.calculate(-177.6, SUBTRACTION, -63.5);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_PositiveAndNegativeNumbers_Ok() {
+        expected = 263.5;
+        actual = myCalculatorTest.calculate(200.0, SUBTRACTION, -63.5);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_ZeroFirstNumberPosition_Ok() {
+        expected = 77.0;
+        actual = myCalculatorTest.calculate(0, SUBTRACTION, -77.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_ZeroSecondNumberPosition_Ok() {
+        expected = 200;
+        actual = myCalculatorTest.calculate(200.0, SUBTRACTION, 0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_MaxValues_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(MAX_VALUE, SUBTRACTION, MAX_VALUE);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void subtraction_MinValues_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(MIN_VALUE, SUBTRACTION, MIN_VALUE);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_PositiveNumbers_Ok() {
+        expected = 50.0;
+        actual = myCalculatorTest.calculate(10.0, MULTIPLICATION, 5.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_NegativeNumbers_Ok() {
+        expected = 50.0;
+        actual = myCalculatorTest.calculate(-10.0, MULTIPLICATION, -5.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_PositiveAndNegativeNumbers_Ok() {
+        expected = -1000.0;
+        actual = myCalculatorTest.calculate(200.0, MULTIPLICATION, -5.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_ZeroFirstNumberPosition_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(0, MULTIPLICATION, 77.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_ZeroSecondNumberPosition_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(200.0, MULTIPLICATION, 0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void multiplication_MaxValues_NotOk() {
+        assertThrows(OperationTypeException.class, () ->
+                myCalculatorTest.calculate(MAX_VALUE, MULTIPLICATION, MAX_VALUE));
+    }
+
+    @Test
+    void multiplication_MinValues_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(MIN_VALUE, MULTIPLICATION, MIN_VALUE);
+        assertEquals(expected, actual, DELTA);
+    }
+
+    @Test
+    void division_PositiveNumbers_Ok() {
+        expected = 1.3923;
+        actual = myCalculatorTest.calculate(90.5, DIVISION, 65.0);
+        assertEquals(expected, actual, DELTA);
+    }
+
+    @Test
+    void division_NegativeNumbers_Ok() {
+        expected = 4.0;
+        actual = myCalculatorTest.calculate(-20.0, DIVISION, -5.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void division_PositiveAndNegativeNumbers_Ok() {
+        expected = -4.0;
+        actual = myCalculatorTest.calculate(20.0, DIVISION, -5.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void division_ZeroFirstNumberPosition_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(0, DIVISION, 77.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void division_ZeroSecondNumberPosition_NotOk() {
+        assertThrows(OperationTypeException.class, () ->
+                myCalculatorTest.calculate(200.0, DIVISION, 0));
+    }
+
+    @Test
+    void division_MaxValues_Ok() {
+        expected = 1.0;
+        actual = myCalculatorTest.calculate(MAX_VALUE, DIVISION, MAX_VALUE);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void division_MinValues_Ok() {
+        expected = 1.0;
+        actual = myCalculatorTest.calculate(MIN_VALUE, DIVISION, MIN_VALUE);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_PositiveValue_PositivePower_Ok() {
+        expected = 400.0;
+        actual = myCalculatorTest.calculate(20.0, RAISING_TO_A_POWER, 2.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_NegativeValue_PositivePower_Ok() {
+        expected = 400.0;
+        actual = myCalculatorTest.calculate(-20.0, RAISING_TO_A_POWER, 2.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_PositiveValue_NegativePower_Ok() {
+        expected = 0.0025;
+        actual = myCalculatorTest.calculate(20.0, RAISING_TO_A_POWER, -2.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_NegativeValue_NegativePower_Ok() {
+        expected = 0.0025;
+        actual = myCalculatorTest.calculate(-20.0, RAISING_TO_A_POWER, -2.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_PositiveValue_ZeroPower_Ok() {
+        expected = 1.0;
+        actual = myCalculatorTest.calculate(20.0, RAISING_TO_A_POWER, 0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_NegativeValue_ZeroPower_Ok() {
+        expected = 1.0;
+        actual = myCalculatorTest.calculate(-20.0, RAISING_TO_A_POWER, 0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void raising_ZeroValue_PositivePower_Ok() {
+        expected = 0;
+        actual = myCalculatorTest.calculate(0, RAISING_TO_A_POWER, 2.0);
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void illegalOperation_NotOk() {
+        assertThrows(OperationTypeException.class, () ->
+                myCalculatorTest.calculate(65.0, '!', 50.0));
+    }
+}