Bael-1305: A Guide to Java Loops (#3181)

* BAEL-1305: A Simple Guide to Java Loops.

* BAEL-1305: Updated article to add few more examples.

core-java/src/test/java/com/baeldung/loops/WhenUsingLoops.java

@@ -1,11 +1,38 @@
 package com.baeldung.loops;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
 import org.junit.Assert;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 public class WhenUsingLoops {
 
     private LoopsInJava loops = new LoopsInJava();
+    private static List<String> list = new ArrayList<>();
+    private static Set<String> set = new HashSet<>();
+    private static Map<String, Integer> map = new HashMap<>();
+
+    @BeforeClass
+    public static void setUp() {
+        list.add("One");
+        list.add("Two");
+        list.add("Three");
+
+        set.add("Four");
+        set.add("Five");
+        set.add("Six");
+
+        map.put("One", 1);
+        map.put("Two", 2);
+        map.put("Three", 3);
+    }
 
     @Test
     public void shouldRunForLoop() {
@@ -34,4 +61,47 @@ public class WhenUsingLoops {
         int[] actual = loops.do_while_loop();
         Assert.assertArrayEquals(expected, actual);
     }
+
+    @Test
+    public void whenUsingSimpleFor_shouldIterateList() {
+        for (int i = 0; i < list.size(); i++) {
+            System.out.println(list.get(i));
+        }
+    }
+
+    @Test
+    public void whenUsingEnhancedFor_shouldIterateList() {
+        for (String item : list) {
+            System.out.println(item);
+        }
+    }
+
+    @Test
+    public void whenUsingEnhancedFor_shouldIterateSet() {
+        for (String item : set) {
+            System.out.println(item);
+        }
+    }
+
+    @Test
+    public void whenUsingEnhancedFor_shouldIterateMap() {
+        for (Entry<String, Integer> entry : map.entrySet()) {
+            System.out.println("Key: " + entry.getKey() + " - " + "Value: " + entry.getValue());
+        }
+    }
+
+    @Test
+    public void whenUsingSimpleFor_shouldRunLabelledLoop() {
+        aa: for (int i = 1; i <= 3; i++) {
+            if (i == 1)
+                continue;
+            bb: for (int j = 1; j <= 3; j++) {
+                if (i == 2 && j == 2) {
+                    break aa;
+                }
+                System.out.println(i + " " + j);
+            }
+        }
+    }
+
 }