listing 1
// Demonstrate a simple main menu. 
   
import java.awt.*;   
import java.awt.event.*;   
import javax.swing.*;   
    
class MenuDemo implements ActionListener { 
   
  JLabel jlab; 
  
  MenuDemo() {   
    // Create a new JFrame container.   
    JFrame jfrm = new JFrame("Menu Demo"); 
   
    // Specify FlowLayout for the layout manager.   
    jfrm.setLayout(new FlowLayout());   
   
    // Give the frame an initial size.   
    jfrm.setSize(220, 200);   
   
    // Terminate the program when the user closes the application.   
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);   
   
    // Create a label that will display the menu selection. 
    jlab = new JLabel(); 
 
    // Create the menu bar. 
    JMenuBar jmb = new JMenuBar(); 
 
    // Create the File menu. 
    JMenu jmFile = new JMenu("File"); 
    JMenuItem jmiOpen = new JMenuItem("Open"); 
    JMenuItem jmiClose = new JMenuItem("Close"); 
    JMenuItem jmiSave = new JMenuItem("Save"); 
    JMenuItem jmiExit = new JMenuItem("Exit"); 
    jmFile.add(jmiOpen); 
    jmFile.add(jmiClose); 
    jmFile.add(jmiSave); 
    jmFile.addSeparator(); 
    jmFile.add(jmiExit); 
    jmb.add(jmFile); 
 
    // Create the Options menu. 
    JMenu jmOptions = new JMenu("Options"); 
 
    // Create the Colors submenu. 
    JMenu jmColors = new JMenu("Colors"); 
    JMenuItem jmiRed = new JMenuItem("Red"); 
    JMenuItem jmiGreen = new JMenuItem("Green"); 
    JMenuItem jmiBlue = new JMenuItem("Blue"); 
    jmColors.add(jmiRed); 
    jmColors.add(jmiGreen); 
    jmColors.add(jmiBlue); 
    jmOptions.add(jmColors); 
 
    // Create the Priority submenu. 
    JMenu jmPriority = new JMenu("Priority"); 
    JMenuItem jmiHigh = new JMenuItem("High"); 
    JMenuItem jmiLow = new JMenuItem("Low"); 
    jmPriority.add(jmiHigh); 
    jmPriority.add(jmiLow); 
    jmOptions.add(jmPriority); 
 
    // Create the Reset menu item. 
    JMenuItem jmiReset = new JMenuItem("Reset"); 
    jmOptions.addSeparator(); 
    jmOptions.add(jmiReset); 
 
    // Finally, add the entire options menu to 
    // the menu bar 
    jmb.add(jmOptions);  
 
    // Create the Help menu. 
    JMenu jmHelp = new JMenu("Help"); 
    JMenuItem jmiAbout = new JMenuItem("About"); 
    jmHelp.add(jmiAbout); 
    jmb.add(jmHelp);  
 
    // Add action listeners for the menu items. 
    jmiOpen.addActionListener(this); 
    jmiClose.addActionListener(this); 
    jmiSave.addActionListener(this); 
    jmiExit.addActionListener(this); 
    jmiRed.addActionListener(this); 
    jmiGreen.addActionListener(this); 
    jmiBlue.addActionListener(this); 
    jmiHigh.addActionListener(this); 
    jmiLow.addActionListener(this); 
    jmiReset.addActionListener(this); 
    jmiAbout.addActionListener(this); 
 
    // Add the label to the content pane. 
    jfrm.add(jlab);    
 
    // Add the menu bar to the frame. 
    jfrm.setJMenuBar(jmb);    
   
    // Display the frame.   
    jfrm.setVisible(true);   
  }   
 
  // Handle menu item action events. 
  public void actionPerformed(ActionEvent ae) {  
    // Get the action command from the menu selection. 
    String comStr = ae.getActionCommand(); 
 
    // If user chooses Exit, then exit the program. 
    if(comStr.equals("Exit")) System.exit(0); 
 
    // Otherwise, display the selection. 
    jlab.setText(comStr + " Selected"); 
  }  
    
  public static void main(String args[]) {   
    // Create the frame on the event dispatching thread.   
    SwingUtilities.invokeLater(new Runnable() {   
      public void run() {   
        new MenuDemo();   
      }   
    });   
  }   
}

listing 2
// Create the File menu with mnemonics and accelerators. 
JMenu jmFile = new JMenu("File"); 
jmFile.setMnemonic(KeyEvent.VK_F); 
 
JMenuItem jmiOpen = new JMenuItem("Open", 
                                  KeyEvent.VK_O); 
jmiOpen.setAccelerator( 
          KeyStroke.getKeyStroke(KeyEvent.VK_O, 
                                 InputEvent.CTRL_DOWN_MASK)); 
 
JMenuItem jmiClose = new JMenuItem("Close", 
                                   KeyEvent.VK_C); 
jmiClose.setAccelerator( 
          KeyStroke.getKeyStroke(KeyEvent.VK_C, 
                                 InputEvent.CTRL_DOWN_MASK)); 
 
JMenuItem jmiSave = new JMenuItem("Save", 
                                  KeyEvent.VK_S); 
jmiSave.setAccelerator( 
          KeyStroke.getKeyStroke(KeyEvent.VK_S, 
                                 InputEvent.CTRL_DOWN_MASK)); 
 
JMenuItem jmiExit = new JMenuItem("Exit", 
                                  KeyEvent.VK_E); 
jmiExit.setAccelerator( 
          KeyStroke.getKeyStroke(KeyEvent.VK_E, 
                                 InputEvent.CTRL_DOWN_MASK));

listing 3
ImageIcon icon = new ImageIcon("AboutIcon.gif"); 
JMenuItem jmiAbout = new JMenuItem("About", icon);

listing 4
jmiAbout.setToolTipText("Info about the MenuDemo program.");

listing 5
// Create the Options menu. 
JMenu jmOptions = new JMenu("Options"); 
 
// Create the Colors submenu. 
JMenu jmColors = new JMenu("Colors"); 
 
// Use check boxes for colors. This allows 
// the user to select more than one color. 
JCheckBoxMenuItem jmiRed = new JCheckBoxMenuItem("Red"); 
JCheckBoxMenuItem jmiGreen = new JCheckBoxMenuItem("Green"); 
JCheckBoxMenuItem jmiBlue = new JCheckBoxMenuItem("Blue"); 
 
jmColors.add(jmiRed); 
jmColors.add(jmiGreen); 
jmColors.add(jmiBlue); 
jmOptions.add(jmColors); 
 
// Create the Priority submenu. 
JMenu jmPriority = new JMenu("Priority"); 
 
// Use radio buttons for the priority setting. 
// This lets the menu show which priority is used 
// but also ensures that one and only one priority 
// can be selected at any one time.  Notice that 
// the High radio button is initially selected. 
JRadioButtonMenuItem jmiHigh = 
  new JRadioButtonMenuItem("High", true); 
JRadioButtonMenuItem jmiLow = 
  new JRadioButtonMenuItem("Low"); 
 
jmPriority.add(jmiHigh); 
jmPriority.add(jmiLow); 
jmOptions.add(jmPriority); 
 
// Create button group for the radio button menu items. 
ButtonGroup bg = new ButtonGroup(); 
bg.add(jmiHigh); 
bg.add(jmiLow); 
 
// Create the Reset menu item. 
JMenuItem jmiReset = new JMenuItem("Reset"); 
jmOptions.addSeparator(); 
jmOptions.add(jmiReset); 
 
// Finally, add the entire options menu to 
// the menu bar 
jmb.add(jmOptions); 

listing 6
// Create an Edit popup menu. 
jpu = new JPopupMenu(); 
 
// Create the popup menu items 
JMenuItem jmiCut = new JMenuItem("Cut"); 
JMenuItem jmiCopy = new JMenuItem("Copy"); 
JMenuItem jmiPaste = new JMenuItem("Paste"); 
 
// Add the menu items to the popup menu. 
jpu.add(jmiCut); 
jpu.add(jmiCopy); 
jpu.add(jmiPaste); 
 
// Add a listener for for the popup trigger. 
jfrm.addMouseListener(new MouseAdapter() {  
  public void mousePressed(MouseEvent me) { 
    if(me.isPopupTrigger())  
      jpu.show(me.getComponent(), me.getX(), me.getY()); 
  }  
  public void mouseReleased(MouseEvent me) { 
    if(me.isPopupTrigger())  
      jpu.show(me.getComponent(), me.getX(), me.getY()); 
  }  
}); 

listing 7
jmiCut.addActionListener(this);  
jmiCopy.addActionListener(this);  
jmiPaste.addActionListener(this); 

listing 8
// Create a Debug tool bar. 
JToolBar jtb = new JToolBar("Debug"); 
 
// Load the images. 
ImageIcon set = new ImageIcon("setBP.gif"); 
ImageIcon clear = new ImageIcon("clearBP.gif"); 
ImageIcon resume = new ImageIcon("resume.gif"); 
 
// Create the tool bar buttons. 
JButton jbtnSet = new JButton(set); 
jbtnSet.setActionCommand("Set Breakpoint"); 
jbtnSet.setToolTipText("Set Breakpoint"); 
 
JButton jbtnClear = new JButton(clear);  
jbtnClear.setActionCommand("Clear Breakpoint"); 
jbtnClear.setToolTipText("Clear Breakpoint"); 
 
JButton jbtnResume = new JButton(resume); 
jbtnResume.setActionCommand("Resume"); 
jbtnResume.setToolTipText("Resume"); 
 
// Add the buttons to the toolbar. 
jtb.add(jbtnSet); 
jtb.add(jbtnClear); 
jtb.add(jbtnResume); 
 
// Add the tool bar to the north position of 
// the content pane. 
jfrm.add(jtb, BorderLayout.NORTH);

listing 9
// Add the tool bar action listeners. 
jbtnSet.addActionListener(this); 
jbtnClear.addActionListener(this); 
jbtnResume.addActionListener(this);

listing 10
// A class to create an action for the Debug menu 
// and tool bar. 
class DebugAction extends AbstractAction { 
  public DebugAction(String name, Icon image, int mnem, 
                    int accel, String tTip) { 
    super(name, image); 
    putValue(ACCELERATOR_KEY, 
             KeyStroke.getKeyStroke(accel,  
                                    InputEvent.CTRL_DOWN_MASK));  
    putValue(MNEMONIC_KEY, mnem); 
    putValue(SHORT_DESCRIPTION, tTip); 
  } 
 
  // Handle events for both the tool bar and the 
  // Debug menu. 
  public void actionPerformed(ActionEvent ae) {     
    String comStr = ae.getActionCommand();  
 
    jlab.setText(comStr + " Selected"); 
 
    // Toggle the enabled status of the 
    // Set and Clear Breakpoint options. 
    if(comStr.equals("Set Breakpoint")) { 
      clearAct.setEnabled(true); 
      setAct.setEnabled(false); 
    } else if(comStr.equals("Clear Breakpoint")) { 
      clearAct.setEnabled(false); 
      setAct.setEnabled(true); 
    } 
  } 
}

listing 11
DebugAction setAct; 
DebugAction clearAct; 
DebugAction resumeAct;

listing 12
// Load the images for the actions. 
ImageIcon setIcon = new ImageIcon("setBP.gif");  
ImageIcon clearIcon = new ImageIcon("clearBP.gif");  
ImageIcon resumeIcon = new ImageIcon("resume.gif"); 

listing 13
// Create actions. 
setAct = 
  new DebugAction("Set Breakpoint", 
                  setIcon, 
                  KeyEvent.VK_S, 
                  KeyEvent.VK_B, 
                  "Set a break point."); 
 
clearAct = 
  new DebugAction("Clear Breakpoint", 
                  clearIcon, 
                  KeyEvent.VK_C, 
                  KeyEvent.VK_L, 
                  "Clear a break point."); 
 
resumeAct = 
  new DebugAction("Resume", 
                  resumeIcon, 
                  KeyEvent.VK_R, 
                  KeyEvent.VK_R, 
                  "Resume execution after breakpoint."); 
 
// Initially disable the Clear Breakpoint option. 
clearAct.setEnabled(false);

listing 14
// Create the tool bar buttons by using the actions.  
JButton jbtnSet = new JButton(setAct); 
JButton jbtnClear = new JButton(clearAct); 
JButton jbtnResume = new JButton(resumeAct); 
  
// Create a Debug tool bar.  
JToolBar jtb = new JToolBar("Breakpoints");  
 
// Add the buttons to the tool bar.  
jtb.add(jbtnSet);  
jtb.add(jbtnClear);  
jtb.add(jbtnResume);  
 
// Add the tool bar to the north position of  
// the content pane.  
jfrm.add(jtb, BorderLayout.NORTH);

listing 15
// Now, create a Debug menu that goes under the Options 
// menu bar item.  Use the actions to create the items. 
JMenu jmDebug = new JMenu("Debug"); 
JMenuItem jmiSetBP = new JMenuItem(setAct); 
JMenuItem jmiClearBP = new JMenuItem(clearAct); 
JMenuItem jmiResume = new JMenuItem(resumeAct); 
jmDebug.add(jmiSetBP); 
jmDebug.add(jmiClearBP); 
jmDebug.add(jmiResume); 
jmOptions.add(jmDebug);

listing 16
// The complete MenuDemo program. 
    
import java.awt.*;    
import java.awt.event.*;    
import javax.swing.*;    
     
class MenuDemo implements ActionListener {  
    
  JLabel jlab;  
 
  JMenuBar jmb; 
 
  JToolBar jtb; 
 
  JPopupMenu jpu; 
 
  DebugAction setAct; 
  DebugAction clearAct; 
  DebugAction resumeAct; 
   
  MenuDemo() {    
    // Create a new JFrame container.    
    JFrame jfrm = new JFrame("Complete Menu Demo");  
    
    // Use default border layout. 
    
    // Give the frame an initial size.    
    jfrm.setSize(360, 200);    
    
    // Terminate the program when the user closes the application.    
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    
    
    // Create a label that will display the menu selection.  
    jlab = new JLabel();  
  
    // Create the menu bar.  
    jmb = new JMenuBar();  
  
    // Make the File menu. 
    makeFileMenu(); 
 
    // Construct the Debug actions. 
    makeActions(); 
 
    // Make the tool bar. 
    makeToolBar(); 
 
    // Make the Options menu.  
    makeOptionsMenu(); 
 
    // Make the Help menu. 
    makeHelpMenu(); 
  
    // Make the Edit popup menu.  
    makeEditPUMenu(); 
 
    // Add a listener for the popup trigger.  
    jfrm.addMouseListener(new MouseAdapter() {   
      public void mousePressed(MouseEvent me) {  
        if(me.isPopupTrigger())   
          jpu.show(me.getComponent(), me.getX(), me.getY());  
      }   
      public void mouseReleased(MouseEvent me) {  
        if(me.isPopupTrigger())   
          jpu.show(me.getComponent(), me.getX(), me.getY());  
      }   
    });  
 
    // Add the label to the center of the content pane.  
    jfrm.add(jlab, SwingConstants.CENTER); 
  
    // Add the tool bar to the north position of  
    // the content pane.  
    jfrm.add(jtb, BorderLayout.NORTH); 
 
    // Add the menu bar to the frame.  
    jfrm.setJMenuBar(jmb);     
    
    // Display the frame.    
    jfrm.setVisible(true);    
  }    
  
  // Handle menu item action events.  
  // This does NOT handle events generated 
  // by the Debug options. 
  public void actionPerformed(ActionEvent ae) {   
    // Get the action command from the menu selection.  
    String comStr = ae.getActionCommand();  
  
    // If user chooses Exit, then exit the program.  
    if(comStr.equals("Exit")) System.exit(0);  
  
    // Otherwise, display the selection.  
    jlab.setText(comStr + " Selected");  
  }   
 
  // An action class for the Debug menu 
  // and tool bar. 
  class DebugAction extends AbstractAction { 
    public DebugAction(String name, Icon image, int mnem, 
                       int accel, String tTip) { 
      super(name, image); 
      putValue(ACCELERATOR_KEY, 
               KeyStroke.getKeyStroke(accel,  
                                      InputEvent.CTRL_DOWN_MASK));  
      putValue(MNEMONIC_KEY, mnem); 
      putValue(SHORT_DESCRIPTION, tTip); 
    } 
 
    // Handle events for both the tool bar and the 
    // Debug menu. 
    public void actionPerformed(ActionEvent ae) {     
      String comStr = ae.getActionCommand();  
 
      jlab.setText(comStr + " Selected"); 
 
      // Toggle the enabled status of the 
      // Set and Clear Breakpoint options. 
      if(comStr.equals("Set Breakpoint")) { 
        clearAct.setEnabled(true); 
        setAct.setEnabled(false); 
      } else if(comStr.equals("Clear Breakpoint")) { 
        clearAct.setEnabled(false); 
        setAct.setEnabled(true); 
      } 
    } 
  } 
 
  // Create the File menu with mnemonics and accelerators.  
  void makeFileMenu() { 
    JMenu jmFile = new JMenu("File");  
    jmFile.setMnemonic(KeyEvent.VK_F);  
 
    JMenuItem jmiOpen = new JMenuItem("Open",  
                                      KeyEvent.VK_O);  
    jmiOpen.setAccelerator(  
              KeyStroke.getKeyStroke(KeyEvent.VK_O,  
                                     InputEvent.CTRL_DOWN_MASK));  
  
    JMenuItem jmiClose = new JMenuItem("Close",  
                                       KeyEvent.VK_C);  
    jmiClose.setAccelerator(  
              KeyStroke.getKeyStroke(KeyEvent.VK_C,  
                                     InputEvent.CTRL_DOWN_MASK));  
  
    JMenuItem jmiSave = new JMenuItem("Save",  
                                      KeyEvent.VK_S);  
    jmiSave.setAccelerator(  
              KeyStroke.getKeyStroke(KeyEvent.VK_S,  
                                     InputEvent.CTRL_DOWN_MASK));  
  
    JMenuItem jmiExit = new JMenuItem("Exit",  
                                      KeyEvent.VK_E);  
    jmiExit.setAccelerator(  
              KeyStroke.getKeyStroke(KeyEvent.VK_E,  
                                     InputEvent.CTRL_DOWN_MASK)); 
 
    jmFile.add(jmiOpen);  
    jmFile.add(jmiClose);  
    jmFile.add(jmiSave);  
    jmFile.addSeparator();  
    jmFile.add(jmiExit);  
    jmb.add(jmFile);  
 
    // Add the action listeners for the File menu. 
    jmiOpen.addActionListener(this);  
    jmiClose.addActionListener(this);  
    jmiSave.addActionListener(this);  
    jmiExit.addActionListener(this);  
  } 
 
  // Create the Options menu.  
  void makeOptionsMenu() { 
    JMenu jmOptions = new JMenu("Options");  
  
    // Create the Colors submenu.  
    JMenu jmColors = new JMenu("Colors");  
  
    // Use check boxes for colors. This allows  
    // the user to select more than one color.  
    JCheckBoxMenuItem jmiRed = new JCheckBoxMenuItem("Red");  
    JCheckBoxMenuItem jmiGreen = new JCheckBoxMenuItem("Green");  
    JCheckBoxMenuItem jmiBlue = new JCheckBoxMenuItem("Blue");  
  
    // Add the items to the Colors menu. 
    jmColors.add(jmiRed);  
    jmColors.add(jmiGreen);  
    jmColors.add(jmiBlue);  
    jmOptions.add(jmColors);  
  
    // Create the Priority submenu.  
    JMenu jmPriority = new JMenu("Priority");  
  
    // Use radio buttons for the priority setting.  
    // This lets the menu show which priority is used  
    // but also ensures that one and only one priority  
    // can be selected at any one time.  Notice thatt  
    // the High radio button is initially selected.  
    JRadioButtonMenuItem jmiHigh =  
      new JRadioButtonMenuItem("High", true);  
    JRadioButtonMenuItem jmiLow =  
      new JRadioButtonMenuItem("Low");  
  
    // Add the items to the Priority menu. 
    jmPriority.add(jmiHigh);  
    jmPriority.add(jmiLow);  
    jmOptions.add(jmPriority);  
 
    // Create a button group for the radio button 
    //  menu items.  
    ButtonGroup bg = new ButtonGroup();  
    bg.add(jmiHigh);  
    bg.add(jmiLow);  
   
    // Now, create a Debug submenu that goes under 
    // the Options menu bar item. Use actions to 
    // create the items. 
    JMenu jmDebug = new JMenu("Debug"); 
    JMenuItem jmiSetBP = new JMenuItem(setAct); 
    JMenuItem jmiClearBP = new JMenuItem(clearAct); 
    JMenuItem jmiResume = new JMenuItem(resumeAct); 
 
    // Add the items to the Debug menu. 
    jmDebug.add(jmiSetBP); 
    jmDebug.add(jmiClearBP); 
    jmDebug.add(jmiResume); 
    jmOptions.add(jmDebug); 
 
    // Create the Reset menu item.  
    JMenuItem jmiReset = new JMenuItem("Reset");  
    jmOptions.addSeparator();  
    jmOptions.add(jmiReset);  
  
    // Finally, add the entire options menu to  
    // the menu bar  
    jmb.add(jmOptions);  
 
    // Add the action listeners for the Options menu, 
    // except for those supported by the Debug menu. 
    jmiRed.addActionListener(this);  
    jmiGreen.addActionListener(this);  
    jmiBlue.addActionListener(this);  
    jmiHigh.addActionListener(this);  
    jmiLow.addActionListener(this);  
    jmiReset.addActionListener(this);  
  } 
 
  // Create the Help menu. 
  void makeHelpMenu() { 
    JMenu jmHelp = new JMenu("Help");  
 
    // Add an icon to the About menu item. 
    ImageIcon icon = new ImageIcon("AboutIcon.gif"); 
 
    JMenuItem jmiAbout = new JMenuItem("About", icon); 
    jmiAbout.setToolTipText("Info about the MenuDemo program."); 
    jmHelp.add(jmiAbout);  
    jmb.add(jmHelp);   
 
    // Add action listener for About. 
    jmiAbout.addActionListener(this);  
  } 
 
  // Construct the actions needed by the Debug menu 
  // and tool bar. 
  void makeActions() { 
    // Load the images for the actions. 
    ImageIcon setIcon = new ImageIcon("setBP.gif");  
    ImageIcon clearIcon = new ImageIcon("clearBP.gif");  
    ImageIcon resumeIcon = new ImageIcon("resume.gif");  
 
    // Create actions. 
    setAct = 
      new DebugAction("Set Breakpoint", 
                      setIcon, 
                      KeyEvent.VK_S, 
                      KeyEvent.VK_B, 
                      "Set a break point."); 
 
    clearAct = 
      new DebugAction("Clear Breakpoint", 
                      clearIcon, 
                      KeyEvent.VK_C, 
                      KeyEvent.VK_L, 
                      "Clear a break point."); 
 
    resumeAct = 
      new DebugAction("Resume", 
                      resumeIcon, 
                      KeyEvent.VK_R, 
                      KeyEvent.VK_R, 
                      "Resume execution after breakpoint."); 
 
    // Initially disable the Clear Breakpoint option. 
    clearAct.setEnabled(false);  
  } 
 
  // Create the Debug tool bar. 
  void makeToolBar() { 
    // Create the tool bar buttons by using the actions.  
    JButton jbtnSet = new JButton(setAct); 
    JButton jbtnClear = new JButton(clearAct); 
    JButton jbtnResume = new JButton(resumeAct); 
  
    // Create the Debug tool bar.  
    jtb = new JToolBar("Breakpoints");  
 
    // Add the buttons to the tool bar.  
    jtb.add(jbtnSet);  
    jtb.add(jbtnClear);  
    jtb.add(jbtnResume);  
  } 
 
  // Create the Edit popup menu. 
  void makeEditPUMenu() { 
    jpu = new JPopupMenu();  
  
    // Create the popup menu items  
    JMenuItem jmiCut = new JMenuItem("Cut");  
    JMenuItem jmiCopy = new JMenuItem("Copy");  
    JMenuItem jmiPaste = new JMenuItem("Paste");  
  
    // Add the menu items to the popup menu.  
    jpu.add(jmiCut);  
    jpu.add(jmiCopy);  
    jpu.add(jmiPaste);  
 
    // Add the Edit popup menu action listeners. 
    jmiCut.addActionListener(this);  
    jmiCopy.addActionListener(this);  
    jmiPaste.addActionListener(this);   
  }  
     
  public static void main(String args[]) {    
    // Create the frame on the event dispatching thread.    
    SwingUtilities.invokeLater(new Runnable() {    
      public void run() {    
        new MenuDemo();    
      }    
    });    
  }    
}