Re: Obtaining a list of all active sessions within a Servlet container.

Hi Theo,

  Use HttpSessionActivationListener as follows for your requirement,

<<

class SessionCounterListener implements HttpSessionActivationListener
{

  public static final Map activeSessions = HashMap<String,
HttpSession>();

  public void sessionDidActivate(HttpSessionEvent event) {
    HttpSession session = event.getSession();
    activeSessions.put(session.getId(), session);
  }

  public void sessionWillPassivate(HttpSessionEvent event) {
    HttpSession session = event.getSession();
    activeSessions.remove(session.getId();
  }

}

Define the above listener in web.xml as,
<listener>
  <listener-class>my.package.SessionCounterListener</listener-class>
</listener>

Use below code to get the active sessions,

SessionCounterListener.activeSessions.size() - Returns the number of
active sessions.
SessionCounterListener.activeSessions.getValues() - Returns the all
the active sessions.