BAEL-5158: Sample App and Unit test for finding ObjectMapper class in a jar.

core-java-modules/core-java-jar/README.md

@@ -8,3 +8,4 @@ This module contains articles about JAR files
 - [Importance of Main Manifest Attribute in a Self-Executing JAR](http://www.baeldung.com/java-jar-executable-manifest-main-class)
 - [Guide to Creating and Running a Jar File in Java](https://www.baeldung.com/java-create-jar)
 - [Get Names of Classes Inside a JAR File](https://www.baeldung.com/jar-file-get-class-names)
+  [Find All Jars Containing Given Class](https://baeldung.com/find-all-jars-containing-given-class/)

core-java-modules/core-java-jar/src/main/java/com/baeldung/jar/JarApp.java

@@ -0,0 +1,18 @@
+package com.baeldung.jar;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import java.net.URL;
+
+public class JarApp {
+
+    public static String findObjectMapperClass() {
+        Class<ObjectMapper> klass = ObjectMapper.class;
+        URL path = klass.getProtectionDomain().getCodeSource().getLocation();
+        return path.toString();
+    }
+
+    public static void main(String[] args) {
+        System.out.println(findObjectMapperClass());
+    }
+}

core-java-modules/core-java-jar/src/test/java/com/baeldung/jar/JarAppUnitTest.java

@@ -0,0 +1,12 @@
+package com.baeldung.jar;
+
+import org.junit.Assert;
+import org.junit.jupiter.api.Test;
+
+public class JarAppUnitTest {
+
+    @Test
+    public void findClassTest(){
+        Assert.assertTrue(JarApp.findObjectMapperClass().endsWith("jackson-databind-2.13.0.jar"));
+    }
+}