Showing visible JPopupMenu in different location does not appear

Question

In my application if a popup menu is already displayed and the user right clicks to reshow the popup menu in a different location the popup menu disappears. I have included a very simple sample app below that shows the problem.
Any suggestions as to what I'm doing wrong gratefully received.
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
public class Test extends JFrame implements MouseListener {
  public static void main(String[] args) {
    Test test = new Test();
    test.setVisible(true);
  JPopupMenu popup;
  public Test() {
    super("Test");
    popup = new JPopupMenu();
    popup.add("Test1");
    popup.add("Test2");
    setSize(400, 300);
    getContentPane().addMouseListener(this);
  public void mouseClicked(MouseEvent e) {
  public void mouseEntered(MouseEvent e) {
  public void mouseExited(MouseEvent e) {
  public void mousePressed(MouseEvent e) {
    popup.show((Component)e.getSource(), e.getX(), e.getY());
  public void mouseReleased(MouseEvent e) {
}

Answer 1

Read the Swing tutorial on [url http://java.sun.com/docs/books/tutorial/uiswing/components/menu.html#popup]How to Use Menus. It shows a better way to check if a popup should be displayed.