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vinay bedidha

Joined: Oct 04, 2001
Posts: 9
i want to transfer control from a servlet to JspPage("Home.jsp")
iam getting a problem when using
RequestDispatcher rd=getServletContext().getRequestDispathcher("/Home.jsp");
iam getting NullPointerException problem.if i use response.sendRedirect("/Home.jsp"); it's working fine.
what's the problem with RequestDispatcher?
David O'Meara

Joined: Mar 06, 2001
Posts: 13459

(This appears to be a continuation of the thread here)
What configuration are you using, is there a web server in front? sendRedirect() forces the browser to make a re-request for the specified page and hence comes from "the outside world". getRequestDispatcher().XXX() loads and returns the respource from the server within the application context.
vinay bedidha

Joined: Oct 04, 2001
Posts: 9
hi David,
Thanks for your answer.
iam using Borland Application server and jsdk2.0.when iam using RequestDispatcher, during compilation time it's giving error message as follows..
unable to Resolve symbol RequestDispathcher rd=getServletContext().getRequestDispatcher("/Home.jsp");
plz help me..
Kyle Brown
Ranch Hand

Joined: Aug 10, 2001
Posts: 3892
Where is "Home.jsp" located with respect to the root of your war file? That might make a difference.
Kyle Brown,
Author of Enterprise Java (tm) Programming with IBM Websphere
See my homepage at for other WebSphere information.

Kyle Brown, Author of Persistence in the Enterprise and Enterprise Java Programming with IBM Websphere, 2nd Edition
See my homepage at for other WebSphere information.
Mike Curwen
Ranch Hand

Joined: Feb 20, 2001
Posts: 3695

There might be a clue in the API

The original problem was that getRequestDispatcher() and request.getRequestDispatcher() seemed to offer different behaviour.

From the API: The difference between this method
[ ie: HttpRequest.getRequestDispatcher(java.lang.String) ]
and ServletContext.getRequestDispatcher(java.lang.String) is that this method can take a relative path.
Mouse Slider

Joined: Nov 02, 2001
Posts: 4
getServletContext().getRequestDispatcher("Home.jsp").include(request, response);
getServletContext().getRequestDispatcher("Home.jsp").forward(request, response);
I agree. Here's the link:
subject: RequestDispathcher
jQuery in Action, 3rd edition