public class Test extends JFrame implements ActionListener
{
  JMenuBar menuBar;
  public Test()
  {
    menuBar = new JMenuBar();

    menuFile = new JMenu("File", false);
    menuBar.add(menuFile);
    menuItem = new JMenuItem("Menu1");
    menuItem.setActionCommand("ACTION_MENU1");
    menuItem.addActionListener(this);
    menuFile.add(menuItem);
    menuFile.addSeparator();

    setJMenuBar(menuBar);
  }

  public void actionPerformed(ActionEvent ae)
  {
    if(ae.getActionCommand().equals("ATION_MENU1"))
    {
      JOptionPane.showMessageDialog(this, "Hello Menu1", "Message", JOptionPane.PLAIN_MESSAGE);
    }
  }
}