Merge pull request #12413 from opokharel/master

[BAEL-5421] by @opokharel

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

@@ -0,0 +1,31 @@
+package com.baeldung.jar;
+
+import java.awt.event.*;
+import java.awt.*;
+
+import javax.swing.*;
+
+public class MySampleGUIAppn extends JFrame {
+    public  MySampleGUIAppn() {
+        if (!GraphicsEnvironment.isHeadless()) {
+            setSize(300,300);
+            setTitle("MySampleGUIAppn");
+            Button b = new Button("Click Me!");
+            b.setBounds(30,100,80,30);
+            add(b);
+            setVisible(true);
+            addWindowListener(new WindowAdapter() {
+                public void windowClosing(WindowEvent e) {
+                    dispose();
+                    System.exit(0);
+                }
+            });
+        }
+        else {
+            System.exit(0);
+        }
+    }
+    public static void main(String[] args) {
+        MySampleGUIAppn app=new  MySampleGUIAppn();
+    }
+}

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

@@ -0,0 +1,15 @@
+package com.baeldung.jar;
+
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+class MySampleGUIAppnUnitTest {
+    @Test
+    void testMain() throws IOException {
+        System.setProperty("java.awt.headless", "true");
+        String [] args = null;
+        System.exit(0);
+        MySampleGUIAppn.main(args);
+    }
+}