1  import java.awt.*;

  2  import javax.swing.*;

  3  

  4  /**

  5     This program demonstrates action objects. Two actions

  6     insert greetings into a text area. Each action can be

  7     triggered by a menu item or toolbar button. When an

  8     action is carried out, the opposite action becomes enabled.

  9  */

 10  public class CommandTester

 11  {

 12     public static void main(String[] args)

 13     {

 14        JFrame frame = new JFrame();

 15        JMenuBar bar = new JMenuBar();

 16        frame.setJMenuBar(bar);

 17        JMenu menu = new JMenu("Say");

 18        bar.add(menu);

 19        JToolBar toolBar = new JToolBar();

 20        frame.add(toolBar, BorderLayout.NORTH);

 21        JTextArea textArea = new JTextArea(10, 40);

 22        frame.add(textArea, BorderLayout.CENTER);

 23  

 24        GreetingAction helloAction = new GreetingAction(

 25              "Hello, World", textArea);

 26        helloAction.putValue(Action.NAME, "Hello");

 27        helloAction.putValue(Action.SMALL_ICON,

 28           new ImageIcon("hello.png"));

 29  

 30        GreetingAction goodbyeAction = new GreetingAction(

 31              "Goodbye, World", textArea);

 32        goodbyeAction.putValue(Action.NAME, "Goodbye");

 33        goodbyeAction.putValue(Action.SMALL_ICON,

 34              new ImageIcon("goodbye.png"));

 35  

 36        helloAction.setOpposite(goodbyeAction);

 37        goodbyeAction.setOpposite(helloAction);

 38        goodbyeAction.setEnabled(false);

 39  

 40        menu.add(helloAction);

 41        menu.add(goodbyeAction);

 42  

 43        toolBar.add(helloAction);

 44        toolBar.add(goodbyeAction);

 45  

 46        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 47        frame.pack();

 48        frame.setVisible(true);

 49     }

 50  }