diff --git a/core-java-modules/core-java-collections-maps-3/src/test/java/com/baeldung/map/computeifabsent/ComputeIfAbsentUnitTest.java b/core-java-modules/core-java-collections-maps-3/src/test/java/com/baeldung/map/computeifabsent/ComputeIfAbsentUnitTest.java
new file mode 100644
index 0000000000..391a059f05
--- /dev/null
+++ b/core-java-modules/core-java-collections-maps-3/src/test/java/com/baeldung/map/computeifabsent/ComputeIfAbsentUnitTest.java
@@ -0,0 +1,39 @@
+package com.baeldung.map.computeifabsent;
+
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+public class ComputeIfAbsentUnitTest {
+
+        @Test
+        public void whenKeyIsPresent_thenFetchTheValue() {
+                Map<String, Integer> stringLength = new HashMap<>();
+                stringLength.put("John", 5);
+                assertEquals((long)stringLength.computeIfAbsent("John", s -> s.length()), 5);
+        }
+
+        @Test
+        public void whenKeyIsNotPresent_thenComputeTheValueUsingMappingFunctionAndStore() {
+                Map<String, Integer> stringLength = new HashMap<>();
+                assertEquals((long)stringLength.computeIfAbsent("John", s -> s.length()), 4);
+                assertEquals((long)stringLength.get("John"), 4);
+        }
+
+        @Test
+        public void whenMappingFunctionReturnsNull_thenDoNotRecordMapping() {
+                Map<String, Integer> stringLength = new HashMap<>();
+                assertEquals(stringLength.computeIfAbsent("John", s -> null), null);
+                assertNull(stringLength.get("John"));
+        }
+
+        @Test(expected = RuntimeException.class)
+        public void whenMappingFunctionThrowsException_thenExceptionIsRethrown() {
+                Map<String, Integer> stringLength = new HashMap<>();
+                stringLength.computeIfAbsent("John", s -> {throw new RuntimeException();});
+        }
+}