A Simple Window Using Frame Example in Java

import javax.swing.*; 
 class TestSimpleFrame 
 { 
            public static void main(String[] args) 
          { 
             SimpleFrame frame = new SimpleFrame(); 
             frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
 frame.setVisible(true); 
       } 
 } 
 class SimpleFrame extends JFrame 
          { 
            private static final int WIDTH = 300; 
            private static final int HEIGHT = 200; 
            public SimpleFrame() 
                    { 
                 setTitle("Simple Frame"); 
                 setSize(WIDTH, HEIGHT); 
            } 
      }