How to do something before the user session expires

Question

Hi,
I need to do some extra cleanup (delete some rows from database, etc) before the session of a user expires.
I tried to do it with Phase Listeners, but haven't figured out how to put it on the session, I guess I need a kind of Listener.

Answer 1

Can implement ServletContextListener to fire off events on context destroy.
example.
   public class LifeCycleServletContextListener
      implements ServletContextListener {
      public LifeCycleServletContextListener() {
      public void contextInitialized(
        ServletContextEvent sce) {
         System.out.println(
           "LifeCycleServletContextListener:
               contextInitialized");
      public void contextDestroyed(
        ServletContextEvent sce) {
         System.out.println(
           "LifeCycleServletContextListener:
               contextDestroyed");
   }