The correct approach to intercept TAB key

Dear Experts,
I have developed a GUI out of javax.swing. The GUI consists of JFrame, several JPanels and javax components, such as JTextField, JLabel, JComboBox, JTable and many more.
Now, I want to change the behavior when user presses TAB key. By default TAB key moves focus from a component to another component. How can I disable this?
I come to two alternatives that I am not sure which one is the correct approach. Could you please advise me?
Alternative 1.
Use key binding on GlassPane.
Alternative 2.
Use event-handling on GlassPane.
If those alternatives are not the best one, could you please provide another alternative?
I have tried the following, but they didn't work...
Action doNothing = new AbstractAction() {
public void actionPerformed(ActionEvent e) {
System.out.println("Tab-key is pressed.");
cmbPCode.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_TAB, 0), "doNothing");
cmbPCode.getActionMap().put("doNothing", doNothing);or
getRootPane().getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_TAB, 0), "doNothing");
getRootPane().getActionMap().put("doNothing", doNothing);where cmbPCode is a JComboBox that receives focus when the GUI shows up.
Thanks for your help,
Patrick
Edited by: Patrick_Stiady on Mar 31, 2009 6:51 AM

Thank you for the advice. I am developing an application where the user is not computer literated, so that I have to limit functional key as many as possible and only allow several keys to be active. For example, I don't want TAB key to change the focus, instead I want TAB key to do nothing.
I have tried keybinding, because I think this is the most relevant, but somehow I failed to recognize which component should be bound with keybinding. I have tried to change the input map of the component that receives the focus when the GUI is displayed (cmbPCode) as can be seen on my first post. I also tried to change the input map of the root pane. Both are not successful.
Now, I wonder whether
1. it does not work because the key is not consume()?
2. Or should I use key listener, which I would only use if keybinding were unable to serve my goal?
3. Or should I learn how to intercept key on the glass pane?
4. Is keybinding able to nullify default action, such as changing focus by TAB key? I am asking this, because I'm going to nullify other important key such as ENTER key.
Thank you for any guidance,
Patrick

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