//Use an anonymous class to register a window
    // listener on the Frame.  This class extends
    // WindowAdapter
    addWindowListener(new WindowAdapter()
      {//begin class definition
        //Instance initializer
        {System.out.println(
             "Anonymous window listener class " +
               "name: " + getClass().getName());}

        public void windowClosing(WindowEvent e){
          System.out.println(
                         "Close button clicked");
          System.exit(0);
        }//end windowClosing
      }//end class definition
    );//end addWindowListener

    setVisible(true);

  }//end constructor

}//end GUI class