diff --git a/core-java-modules/core-java-collections-3/src/test/java/com/baeldung/collections/mapfirstpair/MapFirstPairUnitTest.java b/core-java-modules/core-java-collections-3/src/test/java/com/baeldung/collections/mapfirstpair/MapFirstPairUnitTest.java
new file mode 100644
index 0000000000..b25e0932d8
--- /dev/null
+++ b/core-java-modules/core-java-collections-3/src/test/java/com/baeldung/collections/mapfirstpair/MapFirstPairUnitTest.java
@@ -0,0 +1,143 @@
+package com.baeldung.collections.mapfirstpair;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+import java.util.AbstractMap;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+
+import org.junit.Test;
+
+public class MapFirstPairUnitTest {
+
+    private Map.Entry<Integer, String> getFirstPairUsingIterator(Map<Integer, String> map) {
+        if (map == null || map.size() == 0)
+            return null;
+
+        Iterator<Map.Entry<Integer, String>> iterator = map.entrySet()
+            .iterator();
+
+        if (iterator.hasNext())
+            return iterator.next();
+
+        return null;
+    }
+
+    private Map.Entry<Integer, String> getFirstPairUsingStream(Map<Integer, String> map) {
+        if (map == null || map.size() == 0)
+            return null;
+
+        Set<Map.Entry<Integer, String>> entrySet = map.entrySet();
+
+        return entrySet.stream()
+            .findFirst()
+            .get();
+    }
+
+    private Map<Integer, String> populateMapValues(Map<Integer, String> map) {
+        if (map != null) {
+            map.put(5, "A");
+            map.put(1, "B");
+            map.put(2, "C");
+        }
+        return map;
+    }
+
+    @Test
+    public void whenUsingIteratorForHashMap_thenFirstPairWhichWasNotInsertedFirst() {
+        Map<Integer, String> hashMap = new HashMap<>();
+        hashMap = populateMapValues(hashMap);
+
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingIterator(hashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(1, "B");
+        Map.Entry<Integer, String> pairInsertedFirst = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+        assertNotEquals(pairInsertedFirst, actualValue);
+    }
+
+    @Test
+    public void whenUsingStreamForHashMap_thenFirstPairWhichWasNotInsertedFirst() {
+        Map<Integer, String> hashMap = new HashMap<>();
+        hashMap = populateMapValues(hashMap);
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingStream(hashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(1, "B");
+        Map.Entry<Integer, String> pairInsertedFirst = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+        assertNotEquals(pairInsertedFirst, actualValue);
+    }
+
+    @Test
+    public void whenUsingIteratorForLinkedHashMap_thenFirstPairWhichWasInsertedFirst() {
+        Map<Integer, String> linkedHashMap = new LinkedHashMap<>();
+        linkedHashMap = populateMapValues(linkedHashMap);
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingIterator(linkedHashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+    }
+
+    @Test
+    public void whenUsingStreamForLinkedHashMap_thenFirstPairWhichWasInsertedFirst() {
+        Map<Integer, String> linkedHashMap = new LinkedHashMap<>();
+        linkedHashMap = populateMapValues(linkedHashMap);
+
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingStream(linkedHashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+    }
+
+    @Test
+    public void whenAddedAnElementInHashMap_thenFirstPairChangedUsingIterator() {
+        Map<Integer, String> hashMap = new HashMap<>();
+        hashMap = populateMapValues(hashMap);
+
+        hashMap.put(0, "D");
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingIterator(hashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(0, "D");
+
+        assertEquals(expectedValue, actualValue);
+    }
+
+    @Test
+    public void whenAddedAnElementInHashMap_thenFirstPairChangedUsingStream() {
+        Map<Integer, String> hashMap = new HashMap<>();
+        hashMap = populateMapValues(hashMap);
+
+        hashMap.put(0, "D");
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingStream(hashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(0, "D");
+
+        assertEquals(expectedValue, actualValue);
+    }
+
+    @Test
+    public void whenAddedAnElementInLinkedHashMap_thenFirstPairRemainUnchangedUsingIterator() {
+        Map<Integer, String> linkedHashMap = new LinkedHashMap<>();
+        linkedHashMap = populateMapValues(linkedHashMap);
+
+        linkedHashMap.put(0, "D");
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingIterator(linkedHashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+    }
+
+    @Test
+    public void whenAddedAnElementInLinkedHashMap_thenFirstPairRemainUnchangedUsingStream() {
+        Map<Integer, String> linkedHashMap = new LinkedHashMap<>();
+        linkedHashMap = populateMapValues(linkedHashMap);
+
+        linkedHashMap.put(0, "D");
+        Map.Entry<Integer, String> actualValue = getFirstPairUsingStream(linkedHashMap);
+        Map.Entry<Integer, String> expectedValue = new AbstractMap.SimpleEntry<Integer, String>(5, "A");
+
+        assertEquals(expectedValue, actualValue);
+    }
+}