Menu not activated from mnemonic

Question

Hello All,
Please consider the following code.
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
public class Test extends JFrame{
    public Test()
        try {
          jbInit();
        catch(Exception e) {
          e.printStackTrace();
    public static void main(String[] argv)
        new Test();
    private void jbInit() throws Exception {
//      new MyKeyboardFocusManager();
      JMenuBar menuBar = new JMenuBar();
      JMenu menu = new JMenu("File");
      JMenuItem menuItem = new JMenuItem("Test");
      menu.setMnemonic(70);
      menu.add(menuItem);
      menuBar.add(menu);
      this.setSize(200,100);
      this.setJMenuBar(menuBar);
      this.show();
    class MyKeyboardFocusManager extends DefaultKeyboardFocusManager
        public MyKeyboardFocusManager()
            KeyboardFocusManager.setCurrentKeyboardFocusManager(this);
        public boolean dispatchKeyEvent(KeyEvent event)
            Component component = event.getComponent();
            System.out.println("dispatchKeyEvent > component dispatching the KeyEvent : " + component.getClass().getName());
            return super.dispatchKeyEvent(event);
        public void processKeyEvent(Component component, KeyEvent event)
            System.out.println("processKeyEvent > component processing the KeyEvent : " +
                               component.getClass().getName());
            super.processKeyEvent(component,event);
}If you run the code a simple JFrame will appear with a menu. If you press <Alt-F> the File menu will open. Standard stuff.
Now uncomment the //new MyKeyboardFocusManager(); line and run the code again. The menu no longer activates on the <Alt-F> key event. What is going on????
The MyKeyboardFocusManager class simple prints out some text and forwards the event to the parent. Why should this stop the frame activating the menu????
To make things even more confusing. If you add a component to the JFrame and move the focus to the component, the <Alt-F> key event works and the menu is shown.
Any help appreciated as I am very confused.....
nes

Answer 1

Since you are using your own KeyboardFocusManager that is not handling events by calling super.<method()>. I think you should write your MyKeyboardFocusManager as given below:-
     class MyKeyboardFocusManager extends DefaultKeyboardFocusManager
          KeyboardFocusManager kfm = KeyboardFocusManager.getCurrentKeyboardFocusManager();
          public MyKeyboardFocusManager()
               KeyboardFocusManager.setCurrentKeyboardFocusManager(this);
          public boolean dispatchKeyEvent(KeyEvent event)
               Component component = event.getComponent();
               System.out.println("dispatchKeyEvent > component dispatching the KeyEvent : " +
                    component.getClass().getName());
               return kfm.dispatchKeyEvent(event);
//               return super.dispatchKeyEvent(event);
          public void processKeyEvent(Component component,KeyEvent event)
               System.out.println("processKeyEvent > component processing the KeyEvent : " +
                    component.getClass().getName());
//               super.processKeyEvent(component,event);
               kfm.processKeyEvent(component,event);
     }