FULL PRODUCT VERSION :
java version " 1.7.0_03 "
Java(TM) SE Runtime Environment (build 1.7.0_03-b05)
Java HotSpot(TM) 64-Bit Server VM (build 22.1-b02, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Try to remove a tray icon in system tray in a shutdown hook will prevent the vm terminate. The application will hang on the shutdown hook thread.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
You may need to prepare an png file 'icon.png' under D:Run code below and right click the system tray icon -> Exit.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The tray icon removed and java vm terminated
ACTUAL -
tray icon removed but vm will never exit

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------

import java.awt.*;
import java.awt.event.*;
import java.io.*;

import javax.imageio.*;

public class NewClass {

    public static void main(String... args) throws IOException, AWTException {
        final TrayIcon yourTrayIcon = new TrayIcon(ImageIO.read(new File( " D:\\icon.png " )), " Icon " );
        SystemTray.getSystemTray().add(yourTrayIcon);
        final PopupMenu popup = new PopupMenu();
        MenuItem exitItem = new MenuItem( " Exit " );
        popup.add(exitItem);
        exitItem.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                System.exit(0);
            }
        });
        yourTrayIcon.setPopupMenu(popup);
        Runtime.getRuntime().addShutdownHook(new Thread() {

            public void run() {
                try {
                    if (SystemTray.isSupported()) {
                        SystemTray systemTray = SystemTray.getSystemTray();
                        systemTray.remove(yourTrayIcon);
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
remove the tray icon before call System.exit(0) don't have such problem/avoid remove trayicon in shutdown hook