I am having the same problem. The difference for me is that sessions
work in GAE (deployed) but they don't always work on my local GAE
install. For example, if I set an object in the session from an
Filter, I can't retrieve my object through my JSP.

Is this a bug?

On Nov 10, 12:03 pm, IlyaE <ilyaelk...@gmail.com> wrote:
> I'm looking to track a user session if they have "logged in" using my
> own user manager, but i was having trouble passing my user object back
> to the session once the app was deployed. I will give this a shot but
> i wonder if this was because i was redirecting instead of forwarding.
>
> I was doing this in my servlet
>                 List<MyUser> results = (List<MyUser>) 
> query.execute(email,password);
>
>                 if (results.size() == 0) { redirect = "/index.html"; }
>                 else {
>                         req.getSession().setAttribute("user", results.get(0));
>                 }
>
>                 resp.sendRedirect(redirect);
>
> and this in my jsp
> <%
> MyUser u = (MyUser) request.getSession().getAttribute("user");
> if (u != null) {
>         ....} else { %>
>
> User is null
> <% } %>
>
> So i was always getting null even though i was redirected properly.
>
> Can you explain
>
> On Nov 10, 1:36 pm, "Ikai L (Google)" <ika...@google.com> wrote:
>
>
>
> > Ilya,
>
> > Are you looking to persist objects for a lifetime of a session, or are you
> > looking to minimize the logic you are using in your JSPs?
> > As a general design principle, we recommend that you minimize usage of
> > session scope. Variables bound to session scope are serialized and stored to
> > distributed memory, and as a result, it will work best if you use it to pass
> > around small, simple, immutable objects.
>
> > If you're looking to pass a variable to a view, Java Servlets have a concept
> > of page scope as well as session scope. You don't need to store a variable
> > in session scope if you just want to dispatch the request to a JSP. For
> > instance, you can define a Servlet that looks like this:
>
> > public class MyServlet extends HttpServlet {
>
> >    protected void doGet(HttpServletRequest request, HttpServletResponse
> > response) throws ServletException, IOException {
> >      String myVar = "this is a string that will be passed to the JSP";
> >      request.setAttribute("myVar", myVar);
> >      RequestDispatcher dispatcher =
> > request.getRequestDispatcher("/WEB-INF/my.jsp");
>
> >      dispatcher.forward(request, response);
>
> >    }
>
> > }
>
> > In my.jsp, you can now refer to this variable:
>
> > <%@ page isELIgnored="false" %>
> > <body>
> >   <h1>${myVar}</h1>
> > </body>
>
> > Ikai Lan
> > Developer Programs Engineer, Google App Engine
>
> > On Tue, Nov 10, 2009 at 2:39 PM, IlyaE <ilyaelk...@gmail.com> wrote:
>
> > > Well as i found out, session attributes don't always guarantee that
> > > they are sent back to the same JVM thus i keep getting null objects in
> > > my view. While i saw a similar discussion before the only examples i
> > > found were for Python. I'm looking for a simple java example that
> > > saves an object in the servlet and retrieves it in the jsp.
>
> > > On Nov 9, 5:44 pm, victor <victoraco...@gmail.com> wrote:
> > > > What issue are you encountering?
>
> > > > When you make changes to a session object state, make sure to
> > > > explicitly call the session.setAttribute("<you session ID>", <you
> > > > modified session state object>) again.
>
> > > > i think there is an issue discussed about this before.
>
> > > > On Nov 9, 10:58 am, IlyaE <ilyaelk...@gmail.com> wrote:
>
> > > > > Does anyone have a java session handleing example? It seems that
> > > > > saving objects in the session only works locally.

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