import java.awt.*;import java.awt.event.*;import javax.swing.JMenu;import javax.swing.JMenuItem;import javax.swing.JCheckBoxMenuItem;import javax.swing.JRadioButtonMenuItem;import javax.swing.ButtonGroup;import javax.swing.JMenuBar;import javax.swing.KeyStroke;import javax.swing.ImageIcon;import javax.swing.JTextArea;import javax.swing.JScrollPane;import javax.swing.JFrame;/* * This class exists solely to show you what menus look like. * It has no menu-related event handling. */public class MenuLookDemo extends JFrame {    JTextArea output;    JScrollPane scrollPane;    public MenuLookDemo() {        JMenuBar menuBar;        JMenu menu, submenu;        JMenuItem menuItem;        JCheckBoxMenuItem cbMenuItem;        JRadioButtonMenuItem rbMenuItem;        addWindowListener(new WindowAdapter() {            public void windowClosing(WindowEvent e) {                System.exit(0);            }        });        //Add regular components to the window, using the default BorderLayout.        Container contentPane = getContentPane();        output = new JTextArea(5, 30);        output.setEditable(false);        scrollPane = new JScrollPane(output);        contentPane.add(scrollPane, BorderLayout.CENTER);        //Create the menu bar.        menuBar = new JMenuBar();        setJMenuBar(menuBar);        //Build the first menu.        menu = new JMenu("A Menu");        menu.setMnemonic(KeyEvent.VK_A);        menu.getAccessibleContext().setAccessibleDescription(                "The only menu in this program that has menu items");        menuBar.add(menu);        //a group of JMenuItems        menuItem = new JMenuItem("A text-only menu item",                                 KeyEvent.VK_T);        //menuItem.setMnemonic(KeyEvent.VK_T); //used constructor instead        menuItem.setAccelerator(KeyStroke.getKeyStroke(                KeyEvent.VK_1, ActionEvent.ALT_MASK));        menuItem.getAccessibleContext().setAccessibleDescription(                "This doesn't really do anything");        menu.add(menuItem);        menuItem = new JMenuItem("Both text and icon",                                  new ImageIcon("images/middle.gif"));        menuItem.setMnemonic(KeyEvent.VK_B);        menu.add(menuItem);        menuItem = new JMenuItem(new ImageIcon("images/middle.gif"));        menuItem.setMnemonic(KeyEvent.VK_D);        menu.add(menuItem);        //a group of radio button menu items        menu.addSeparator();        ButtonGroup group = new ButtonGroup();        rbMenuItem = new JRadioButtonMenuItem("A radio button menu item");        rbMenuItem.setSelected(true);        rbMenuItem.setMnemonic(KeyEvent.VK_R);        group.add(rbMenuItem);        menu.add(rbMenuItem);        rbMenuItem = new JRadioButtonMenuItem("Another one");        rbMenuItem.setMnemonic(KeyEvent.VK_O);        group.add(rbMenuItem);        menu.add(rbMenuItem);        //a group of check box menu items        menu.addSeparator();        cbMenuItem = new JCheckBoxMenuItem("A check box menu item");        cbMenuItem.setMnemonic(KeyEvent.VK_C);        menu.add(cbMenuItem);        cbMenuItem = new JCheckBoxMenuItem("Another one");        cbMenuItem.setMnemonic(KeyEvent.VK_H);        menu.add(cbMenuItem);        //a submenu        menu.addSeparator();        submenu = new JMenu("A submenu");        submenu.setMnemonic(KeyEvent.VK_S);        menuItem = new JMenuItem("An item in the submenu");        menuItem.setAccelerator(KeyStroke.getKeyStroke(                KeyEvent.VK_2, ActionEvent.ALT_MASK));        submenu.add(menuItem);        menuItem = new JMenuItem("Another item");        submenu.add(menuItem);        menu.add(submenu);        //Build second menu in the menu bar.        menu = new JMenu("Another Menu");        menu.setMnemonic(KeyEvent.VK_N);        menu.getAccessibleContext().setAccessibleDescription(                "This menu does nothing");        menuBar.add(menu);    }    public static void main(String[] args) {        MenuLookDemo window = new MenuLookDemo();        window.setTitle("MenuLookDemo");        window.setSize(450, 260);        window.setVisible(true);    }}