Servlet Session Questions

Question

Hi,everybody:
I'm puzzled by two questions about session in servlet.
1.The default timeout of J2EE example WAR is set to 30sec.Is it too short?
2.in J2EE Tutorial1.3 it says"To ensure that an active session is not timed-out, you should periodically access the session in service methods because this resets the session's time-to-live counter",But I can't see any codes in example servlets to access session "periodically".Could you please explain that?
Thank you!

Answer 1

I,
I have a problem with the session.
After the "getMaxInactiveInterval" time, I reload my servlet , but
the session is lost even if I test it :
Before doing anything, I do this :
HttpSession oSession = req.getSession (=(false);
     if(oSession == null)
// forward to a login_page
RequestDispatcher rd = getServletContext().getRequestDispatcher(
"login_page");
rd.forward(req, res);
// request to the database to get user'characteristics
// and put then in the session
String sUser = (String)oSession.getValue("COD"); // sUser is null !
The pb is that the session has not been removed from the Server after
the MaxInactiveInterval, so when i make a request , I have in the session :
the req.isRequestedSessionIdValid() gives : true .
and a new session is created with a new id
Something very strange.
Thanks for help.