Pc ihm java et keyListener

import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;

public class Key implements KeyListener {

	public Key() {
		JFrame f = new JFrame();
		f.add(new JLabel("Appuis sur entrer"));
		f.addKeyListener(this);
		f.setSize(500, 500);
		f.setVisible(true);
	}

	public void entrer() {
		JOptionPane.showConfirmDialog(null, "Valider", "Message", JOptionPane.PLAIN_MESSAGE);
	}

	public void keyPressed(KeyEvent e) {
		if (e.getKeyCode() == KeyEvent.VK_ENTER) {
			entrer();
		}
	}

	public void keyReleased(KeyEvent e) {
	}

	public void keyTyped(KeyEvent e) {
	}

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