need help with session time our

[Rajini Kand]

<session-config>
<session-timeout>10</session-timeout>
</session-config>

[Abhishek Asthana]

I love cryptic questions but this is a bit over the top
I guess you would want to ASK the question also.

[Rajini Kand]

sorry It got submitted before I even typed the question.

My system just want to go ahead of me

My mistake

[Rajini Kand]

Here is the question

<session-config>
<session-timeout>10</session-timeout>
</session-config>

What really happens at the container side when the session is timed out?

I a configure a sessiontimeout.jsp to be displayed. I want to know if what is the flow from session time out to display of jsp from the container perspective

Is there a difference between session time out and session invalid?

Does the container takes care of session time out or it has to be programatically done?

Is it dependent on the application server?

Thanks in advance

[William Brogden]

As a general statement, when the system notices that the session has been inactive for a period greater than the timeout (I dont know if the API requires this order.
1. container obtains synchronization lock on session
2. the session is marked as invalid
3. all listeners are notified
4. all references held in the session are set to null

Now for the specific - here is the code from Tomcat 5

    /**
     * Perform the internal processing required to invalidate this session,
     * without triggering an exception if the session has already expired.
     *
     * @param notify Should we notify listeners about the demise of
     *  this session?
     */
    public void expire(boolean notify) {
 
        // Mark this session as "being expired" if needed
        if (expiring)
            return;
 
        synchronized (this) {
 
            if (manager == null)
                return;
 
            expiring = true;
        
            // Notify interested application event listeners
            // FIXME - Assumes we call listeners in reverse order
            Context context = (Context) manager.getContainer();
            Object listeners[] = context.getApplicationLifecycleListeners();
            if (notify && (listeners != null)) {
                HttpSessionEvent event =
                    new HttpSessionEvent(getSession());
                for (int i = 0; i < listeners.length; i++) {
                    int j = (listeners.length - 1) - i;
                    if (!(listeners[j] instanceof HttpSessionListener))
                        continue;
                    HttpSessionListener listener =
                        (HttpSessionListener) listeners[j];
                    try {
                        fireContainerEvent(context,
                                           "beforeSessionDestroyed",
                                           listener);
                        listener.sessionDestroyed(event);
                        fireContainerEvent(context,
                                           "afterSessionDestroyed",
                                           listener);
                    } catch (Throwable t) {
                        try {
                            fireContainerEvent(context,
                                               "afterSessionDestroyed",
                                               listener);
                        } catch (Exception e) {
                            ;
                        }
                        manager.getContainer().getLogger().error
                            (sm.getString("standardSession.sessionEvent"), t);
                    }
                }
            }
            accessCount = 0;
            setValid(false);
 
            /*
             * Compute how long this session has been alive, and update
             * session manager's related properties accordingly
             */
            long timeNow = System.currentTimeMillis();
            int timeAlive = (int) ((timeNow - creationTime)/1000);
            synchronized (manager) {
                if (timeAlive > manager.getSessionMaxAliveTime()) {
                    manager.setSessionMaxAliveTime(timeAlive);
                }
                int numExpired = manager.getExpiredSessions();
                numExpired++;
                manager.setExpiredSessions(numExpired);
                int average = manager.getSessionAverageAliveTime();
                average = ((average * (numExpired-1)) + timeAlive)/numExpired;
                manager.setSessionAverageAliveTime(average);
            }
 
            // Remove this session from our manager's active sessions
            manager.remove(this);
 
            // Notify interested session event listeners
            if (notify) {
                fireSessionEvent(Session.SESSION_DESTROYED_EVENT, null);
            }
 
            // We have completed expire of this session
            expiring = false;
 
            // Unbind any objects associated with this session
            String keys[] = keys();
            for (int i = 0; i < keys.length; i++)
                removeAttributeInternal(keys[i], notify);
 
        }
 
    }
   

Thats what I love about open source software you can answer questions like this by looking at the code.

Bill