Getting hang/crash problem when I try to close browser window from applet

Question

I have a small Apllet that has a button that calls a Javascript function in the opening window, to close the window in which it is loaded.
The Applet window is a PopUp window from one of my application's window. First time I start my application and load that Applet the button works fine. It calls the Javascript method and the Method closes the window using the self.close() method.
But now if I open the applet window again and click on the button to close the windows, it hangs. I put in trace statements and saw that it hangs on JSObject.getWindow() window.
I am using JDK Plugin 1.4.2_07 and 5.0 , if I work out on IE browser, it works fine.But when I use firefox or mozilla it gives problem of hanging/crashing.
Note that in case of 1.4.2_07 this problem experienced some times but in case of 5.0 it gives always for other than IE browser.
Please, if somebody could give me some clue about why this would happen, I will really appreciate that. and code related to this is given below
import javax.swing.JApplet;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import netscape.javascript.JSObject;
public class TestApplet extends JApplet implements ActionListener{
protected JButton closeButton = null;
protected JSObject win = null;
private JFrame frame = null;
private boolean alreadyClosed = false;
public void init(){
this.win = JSObject.getWindow(this);
this.closeButton = new JButton("Close Browser Window");
this.add(this.closeButton);
this.closeButton.addActionListener(this);
frame = new JFrame("Test Frame");
frame.setSize(300, 400);
frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.out.println("windowClosing");
alreadyClosed = true;
TestApplet.this.stop();
frame.show();
public void actionPerformed(ActionEvent ae){
stop();
public void stop() {
if (!alreadyClosed) {
alreadyClosed = true;
frame.dispose();
closeLaunchedBrowser();
System.gc();
System.runFinalization();
private void closeLaunchedBrowser() {
final TestApplet thisObject = this;
Runnable r = new Runnable() {
public void run() {
try {
JSObject win = (JSObject)JSObject.getWindow(thisObject);
if (win != null && win.toString() != null) {
//win.eval("top.opener=self;self.close();");
//win.call("close", null);
win.eval("self.close();");
} catch (Exception e) {
Thread t = new Thread(r);
t.start();
Thanks.

Answer 1

I am waiting for any reply. I have tried for all these below options still I am getting Problem. I heard this is because of javascript, it wont call methods more times .Thats
why I need other than JSObject or java script solution.If some one know anything about this or any modifications I have to made for the below options to avoid that problem please let me know.
// URL durl = new URL(thisObject.getCodeBase(), "test/CloseMe.htm");
// System.out.println("URL :" + durl.toString());      
// thisObject.getAppletContext().showDocument(durl);
//     thisObject.getAppletContext().showDocument(new URL("javascript:window.close();"), "_self");
//win.eval("top.opener=self;top.close();");
//win.call("close", null);
//Object[] args = { "close", new Integer(50) };
// win.call("setTimeout", args);
//win.eval("setTimeout("close", new Integer(50));");
If it is the problem of JRE I just need it should work on 1.4.2_01 or higher.
thanks.