Java EE (Java Enterprise Edition) General Discussion

I have an applet that needs to communicate with a servlet telling the servlet to logout once the parent window (web browser) is closed. I am new to programming with GUI's involved so I apologize for any ignorance. I have been searching for an answer on solving this problem for a while and have so far been able to write a simple applet that sends a message back to the servlet once the browser is closed by implementing the stop() function -- however it sends the same message when the back button is pressed. I need to message to be sent only when the browser is closed out.