JPanel can't receive key events

I have a single JPanel added to the content pane of a JFrame.
I want to itercept key events by adding a KeyListener to the JPanel.
If I do it, I don't receive key events.
To solve the problem I identified two ways:
- add the KeyListener to the JFrame's content pane
- invoke setFocusable(true) on the JPanel (available only since 1.4)
I can't use the former because I want to bind the the KeyListener to the JPanel, and I can't use the latter because I don't want to have dependencies on jdk 1.4.
Can anyone suggest a way to solve the problem as simple as calling setFocusable() but available also for older versions of java?

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class KeyListenTest {
     public static void main(String[] args) {
          JPanel panel = new JPanel();
          panel.addKeyListener(new KeyAdapter() {
               public void keyTyped(KeyEvent e) {
                    System.out.println(e);
          JFrame frame = new JFrame();
          frame.getContentPane().add(panel);
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.setSize(400,300);
          frame.setVisible(true);
          panel.requestFocus();
}The panel must be displayable and visible, so you have to make the call after frame.setVisible(true), however if you don't have any other components that will take the focus away from your panel, this should do it for you. If you want the use to be able to shift focus to your panel, then just add a mouse listener to the panel with a mousePressed(MouseEvent) method that calls the requestFocus() method on the panel.

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JPanel can't receive key events

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