1  import java.awt.event.ActionListener;

  2  import javax.swing.JButton;

  3  import javax.swing.JFrame;

  4  

  5  /**

  6     This program demonstrates how to install an action listener.

  7  */

  8  public class ButtonViewer

  9  {  

 10     private static final int FRAME_WIDTH = 100;

 11     private static final int FRAME_HEIGHT = 60;

 12  

 13     public static void main(String[] args)

 14     {  

 15        JFrame frame = new JFrame();

 16        JButton button = new JButton("Click me!");

 17        frame.add(button);

 18       

 19        ActionListener listener = new ClickListener();

 20        button.addActionListener(listener);

 21  

 22        frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);

 23        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 24        frame.setVisible(true);

 25     }

 26  }