Problem doing a reDirect

Question

My application has a Login page which then brings me to my homepage home.jsp
On this page I fill out fields which populates my backing bean and then with some Action I get forwarded to b.jsp
I do other stuff here and everything's fine until ...... I let the app time out and then do some button action on b.jsp.
I get sent to the login page, login and then the browser when attempting to load b.jsp ( My original location ) I get several "Could not get property ...... " servletExceptions. When I debug the bean ( which is session scope ) I see that it has lots of fields which are null because they all get populated in home.jsp but the application is trying to load b.jsp
I thought this could be fixed with a navigation rule but as I'm going to b.jsp straight from login.html no rules will get run.
I put a redirect in the bean to redirect if it detects any of the values it requires are null but this does not work. I get the same "Could not get property ...... " servletException
     private boolean checkForRedirect()
          FacesContext context = FacesContext.getCurrentInstance();
          HttpServletResponse response =     (HttpServletResponse)context.getExternalContext().getResponse();
          try
                    if( ( field1== null ) || ( field2==null ) )
                         response. sendRedirect("home.jsp");
                         return false;
          catch (IOException e)
               e.printStackTrace();//To change body of catch statement use File | Settings | File Templates.
          return true;
     }

Answer 1

Hi JFrain2004,
I was interested in the result of this, so I gave it a test as I have a page that can get an error as described.
So my result..
First, somewhere near the top of the b.jsp page (or xhtml page in my case) put the equivilant of the following (This code must certainly go before any other components):
<h:panelGroup rendered="#{userSession.findPacketContext == null}">
     <script type='text/javascript'>window.location = 'http://www.google.com/'</script>
</h:panelGroup>Change userSession the bean you are using and try and get an important variable from it (one that if you don't have will cause the page to blow up). In my case I need the findPacketContext. Without it the code will blow up. Now the assumption is that if I have been to page "a" first, then findPacketContext is not null, so do check in the h:panelGroup for when it is null. The javascript will be printed when the result is null and will send the page to what ever page you wish, eg. "a.jsp".
Thanks
Victoria