BAEL-3511 : Default parameters in Java (#8317)

* Added Assertj dependency

* Default parameter example POJO and test class

core-java-modules/core-java-lang-2/src/test/java/com/baeldung/defaultparams/TeaUnitTest.java

@@ -0,0 +1,20 @@
+package com.baeldung.defaultparams;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import org.junit.Test;
+
+
+public class TeaUnitTest {
+    
+    @Test
+    public void whenTeaWithOnlyName_thenCreateDefaultTea() {
+        Tea blackTea = new Tea("Black Tea");
+
+        assertThat(blackTea.getName()).isEqualTo("Black Tea");
+        assertThat(blackTea.getMilk()).isEqualTo(0);
+        assertThat(blackTea.isHerbs()).isFalse();
+        assertThat(blackTea.getSugar()).isEqualTo(0);
+        assertThat(blackTea.getTeaPowder()).isEqualTo(Tea.DEFAULT_TEA_POWDER);
+    }
+
+}