The program shows two problems:

1. The componentHidden method does not get called if the applet window is
   covered by another window. It only gets called when the applet window
   gets iconified.

2. The componentMoved method never gets called, no matter how often the
   applet window is moved around.

---------- test case -----


import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class BugInComponentEvent extends Applet implements ComponentListener {

    public void
    init() {
        addComponentListener(this); // ready to hear
    }
    
    public void componentHidden(ComponentEvent ce) { // maybe bug
        System.out.println("hidden");
    }
    public void componentMoved(ComponentEvent ce) { // bug
        System.out.println("moved");
    }
    public void
    componentResized(ComponentEvent ce) { // OK
        System.out.println("resized");
    }
    public void componentShown(ComponentEvent ce) { // maybe bug
        System.out.println("shown");
    }

}