FULL PRODUCT VERSION :
java version "1.5.0_04"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_04-b05)
Java HotSpot(TM) Client VM (build 1.5.0_04-b05, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
When a JMenuBar is added to a JFrame and made invisible at any time via the setVisible() method, the accelerator for the JMenuItem's will also be stopped. The accelerator should still work. It should be 'shutdown' only if the menu is made invisible and is disabled (setEnabled()).

-----------------------
import java.awt.*;
import javax.swing.*;

@SuppressWarnings("serial")
public class MenuBug extends JFrame {

private JToggleButton button;
private JMenuBar menubar;
private int counter;
private JTextArea area;

public MenuBug( ) {
super( );
initFrame( );
setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
}

private void initFrame() {
setLayout( new BorderLayout( ) );

menubar = new JMenuBar( );
setJMenuBar( menubar );

JMenuItem item = new JMenuItem("Test");
item.addActionListener( new ActionListener( ) {
public void actionPerformed(ActionEvent e) {
counter++;
area.append( "\nMenu selected " + counter + " times" );
}
});
item.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_T, KeyEvent.CTRL_MASK ) );

menubar.add( item );

button = new JToggleButton( "MENU ON/OFF" );
button.addActionListener( new ActionListener( ) {
public void actionPerformed(ActionEvent e) {
menubar.setVisible( !menubar.isVisible( ) );
}
});
add( button, BorderLayout.SOUTH );

area = new JTextArea( 10, 15 );
add( area, BorderLayout.CENTER );

pack( );
setVisible( true );
}

public static void main(String[] args) {
new MenuBug();
}
}

---------------------

1) Open the application
2) Use the accelerator of the menu-item (CTRL+T) ; Some text will be appended to the textarea
3) Push the 'Menu On/Off' togglebutton
4) Try the accelerator again


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1) Open the application
2) Use the accelerator of the menu-item (CTRL+T) ; Some text will be appended to the textarea
3) Push the 'Menu On/Off' togglebutton
4) Try the accelerator again

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Expected more text would be appended to the textarea
ACTUAL -
nothing is added, because the actionListener was not listening

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;
import javax.swing.*;

@SuppressWarnings("serial")
public class MenuBug extends JFrame {

private JToggleButton button;
private JMenuBar menubar;
private int counter;
private JTextArea area;

public MenuBug( ) {
super( );
initFrame( );
setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
}

private void initFrame() {
setLayout( new BorderLayout( ) );

menubar = new JMenuBar( );
setJMenuBar( menubar );

JMenuItem item = new JMenuItem("Test");
item.addActionListener( new ActionListener( ) {
public void actionPerformed(ActionEvent e) {
counter++;
area.append( "\nMenu selected " + counter + " times" );
}
});
item.setAccelerator( KeyStroke.getKeyStroke( KeyEvent.VK_T, KeyEvent.CTRL_MASK ) );

menubar.add( item );

button = new JToggleButton( "MENU ON/OFF" );
button.addActionListener( new ActionListener( ) {
public void actionPerformed(ActionEvent e) {
menubar.setVisible( !menubar.isVisible( ) );
}
});
add( button, BorderLayout.SOUTH );

area = new JTextArea( 10, 15 );
add( area, BorderLayout.CENTER );

pack( );
setVisible( true );
}

public static void main(String[] args) {
new MenuBug();
}
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Add a KeyListener to the frame.