Move articles out of core-java-lang part 2

core-java-modules/core-java-lang-operators/README.md

@@ -4,3 +4,4 @@
 - [The Modulo Operator in Java](https://www.baeldung.com/modulo-java)
 - [Java instanceof Operator](https://www.baeldung.com/java-instanceof)
 - [A Guide to Increment and Decrement Unary Operators in Java](https://www.baeldung.com/java-unary-operators)
+- [Java Compound Operators](https://www.baeldung.com/java-compound-operators)

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/compoundoperators/CompoundOperatorsUnitTest.java

@@ -0,0 +1,111 @@
+package com.baeldung.compoundoperators;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class CompoundOperatorsUnitTest {
+
+    @Test
+    public void whenAssignmentOperatorIsUsed_thenValueIsAssigned() {
+        int x = 5;
+
+        assertEquals(5, x);
+    }
+
+    @Test
+    public void whenCompoundAssignmentUsed_thenSameAsSimpleAssignment() {
+        int a = 3, b = 3, c = -2;
+        a = a * c; // Simple assignment operator
+        b *= c; // Compound assignment operator
+
+        assertEquals(a, b);
+    }
+
+    @Test
+    public void whenAssignmentOperatorIsUsed_thenValueIsReturned() {
+        long x = 1;
+        long y = (x+=2);
+
+        assertEquals(3, y);
+        assertEquals(y, x);
+    }
+
+    @Test
+    public void whenCompoundOperatorsAreUsed_thenOperationsArePerformedAndAssigned() {
+        //Simple assignment
+        int x = 5; //x is 5
+
+        //Incrementation
+        x += 5; //x is 10
+        assertEquals(10, x);
+
+        //Decrementation
+        x -= 2; //x is 8
+        assertEquals(8, x);
+
+        //Multiplication
+        x *= 2; //x is 16
+        assertEquals(16, x);
+
+        //Division
+        x /= 4; //x is 4
+        assertEquals(4, x);
+
+        //Modulus
+        x %= 3; //x is 1
+        assertEquals(1, x);
+
+
+        //Binary AND
+        x &= 4; //x is 0
+        assertEquals(0, x);
+
+        //Binary exclusive OR
+        x ^= 4; //x is 4
+        assertEquals(4, x);
+
+        //Binary inclusive OR
+        x |= 8; //x is 12
+        assertEquals(12, x);
+
+
+        //Binary Left Shift
+        x <<= 2; //x is 48
+        assertEquals(48, x);
+
+        //Binary Right Shift
+        x >>= 2; //x is 12
+        assertEquals(12, x);
+
+        //Shift right zero fill
+        x >>>= 1; //x is 6
+        assertEquals(6, x);
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void whenArrayIsNull_thenThrowNullException() {
+        int[] numbers = null;
+
+        //Trying Incrementation
+        numbers[2] += 5;
+    }
+
+    @Test(expected = ArrayIndexOutOfBoundsException.class)
+    public void whenArrayIndexNotCorrect_thenThrowArrayIndexException() {
+        int[] numbers = {0, 1};
+
+        //Trying Incrementation
+        numbers[2] += 5;
+    }
+
+    @Test
+    public void whenArrayIndexIsCorrect_thenPerformOperation() {
+        int[] numbers = {0, 1};
+
+        //Incrementation
+        numbers[1] += 5;
+        assertEquals(6, numbers[1]);
+    }
+
+}

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/diamondoperator/Car.java

@@ -1,4 +1,4 @@
-package com.baeldung.java.diamond;
+package com.baeldung.diamondoperator;
 
 public class Car<T extends Engine> implements Vehicle<T> {
 

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/diamondoperator/DiamondOperatorUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.java.diamond;
+package com.baeldung.diamondoperator;
 
 import static org.junit.Assert.assertNotNull;
 

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/diamondoperator/Diesel.java

@@ -1,4 +1,4 @@
-package com.baeldung.java.diamond;
+package com.baeldung.diamondoperator;
 
 public class Diesel implements Engine {
 

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/diamondoperator/Engine.java

@@ -1,4 +1,4 @@
-package com.baeldung.java.diamond;
+package com.baeldung.diamondoperator;
 
 public interface Engine {
 

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/diamondoperator/Vehicle.java

@@ -1,4 +1,4 @@
-package com.baeldung.java.diamond;
+package com.baeldung.diamondoperator;
 
 public interface Vehicle<T extends Engine> {
 

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/java/doublebrace/DoubleBraceUnitTest.java

@@ -1,46 +0,0 @@
-package com.baeldung.java.doublebrace;
-
-import org.junit.Test;
-
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.Set;
-import java.util.stream.Stream;
-
-import static java.util.stream.Collectors.collectingAndThen;
-import static java.util.stream.Collectors.toSet;
-import static org.junit.Assert.assertTrue;
-
-public class DoubleBraceUnitTest {
-
-    @Test
-    public void whenInitializeSetWithoutDoubleBraces_containsElements() {
-        final Set<String> countries = new HashSet<>();
-        countries.add("India");
-        countries.add("USSR");
-        countries.add("USA");
-        assertTrue(countries.contains("India"));
-    }
-
-    @Test
-    public void whenInitializeSetWithDoubleBraces_containsElements() {
-        final Set<String> countries = new HashSet<String>() {
-
-            {
-                add("India");
-                add("USSR");
-                add("USA");
-            }
-        };
-        assertTrue(countries.contains("India"));
-    }
-
-    @Test
-    public void whenInitializeUnmodifiableSetWithDoubleBrace_containsElements() {
-         Set<String> countries = Stream.of("India", "USSR", "USA")
-           .collect(collectingAndThen(toSet(), Collections::unmodifiableSet));
-
-        assertTrue(countries.contains("India"));
-    }
-
-}

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/keyword/InstanceOfUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.keyword.test;
+package com.baeldung.keyword;
 
 import org.junit.Assert;
 import org.junit.jupiter.api.Test;