BAEL-6418 (#14311)

* BAEL-6418

This commit aims to add a test class for the article BAEL-6418

* Update IntegerClassIntegerTYPEIntClassUnitTest.java

* Update IntegerClassIntegerTYPEIntClassUnitTest.java

* Update IntegerClassIntegerTYPEIntClassUnitTest.java

* Update IntegerClassIntegerTYPEIntClassUnitTest.java

core-java-modules/core-java-numbers-6/src/test/java/com/baeldung/integerclassintegertypeintclass/IntegerClassIntegerTYPEIntClassUnitTest.java

@@ -0,0 +1,45 @@
+package com.baeldung.integerclassintegertypeintclass;
+
+import org.junit.Test;
+import org.junit.jupiter.api.Assertions;
+
+public class IntegerClassIntegerTYPEIntClassUnitTest {
+
+    @Test
+    public void givenIntegerClass_whenGetName_thenVerifyClassName() {
+        Class<Integer> integerClass = Integer.class;
+        Assertions.assertEquals("java.lang.Integer", integerClass.getName());
+        Assertions.assertEquals(Number.class, integerClass.getSuperclass());
+        Assertions.assertFalse(integerClass.isPrimitive());
+    }
+
+    public int sum(int a, int b) {
+        return a + b;
+    }
+
+    public int sum(Integer a, Integer b) {
+        return a + b;
+    }
+
+    public int sum(int a, Integer b) {
+        return a + b;
+    }
+
+    @Test
+    public void givenIntAndInteger_whenAddingValues_thenVerifySum() {
+        int primitiveValue = 10;
+        Integer wrapperValue = Integer.valueOf(primitiveValue);
+        Assertions.assertEquals(20, sum(primitiveValue, primitiveValue));
+        Assertions.assertEquals(20, sum(primitiveValue, wrapperValue));
+        Assertions.assertEquals(20, sum(wrapperValue, wrapperValue));
+        Assertions.assertEquals(Integer.TYPE.getName(), int.class.getName());
+    }
+
+    @Test
+    public void givenIntValue_whenUsingIntClass_thenVerifyIntClassProperties() {
+        Class<?> intClass = int.class;
+        Assertions.assertEquals("int", intClass.getName());
+        Assertions.assertTrue(intClass.isPrimitive());
+        Assertions.assertEquals(int.class, intClass);
+    }
+}