I have just recently merged in the issue...

My results (not necessarily perfect :) are:
- all listener objects are to be declared in web.xml;
- it seems they are instantiated automatically along with the web app;
- it may be a good idea to implement a listener as a special class,
independent of any servlets;
- a good servlet-to-listener communication point is ServletContext;
- to arrange this communication a listener may implement also
ServletContextListener and in its contextInitialized() register itself with
the ServletContext using setAttribute ();
- a servlet can then get reference to the listener via
getServletContext().getAttribute();

The reason of your troubles (if I understood you correct) may be that you
really have two servlet+listener instances. One is instantiated as listener
an so its "init" is never invoked; the other is instantiated as servlet and
does not get listener events.

Regards,
Sergey

----- Original Message -----
From: "Ralf Mitschke" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, June 12, 2002 2:41 AM
Subject: Listener Objects


> Hi!
>
> I would like to know how Listener Objects are instantiated.
>
> And here's my reason :-)
> My Class extends HttpServlet and I tried to deal with SessionEvents in the
same Class.
> So I implemented HttpSessionListener.
> But when the sessionCreated/sessionDestroyed methods get the Event any
changes made in the Servlet are gone.
>
> For Example: I use a debuging Object of my own, which I instantiate in the
Servlet init method. In sessionCreated the Instance is gone and the
Reference is null.
>
> My Guess is that I am dealing with 2 different Object instaces.
> Are the Listener Objects specified in the web.xml instantiated for
themselves?
>
> If so, i could split the Class and encapsulate the session stuff I need to
do in another Object.
> But could you suggest a method to communicate between my servlet and my
sessionListener?
>
> Thanks for your time :-)
>
> Ralf
>
>
>
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