Get values from a servlet

[Sam Maivia]

I am trying to a pass a value from a servlet to a jsp. I am getting null pointer exception. Error 503 Service Unavailable.
In the servlets file I send the values as:
request.setAttribute("error", "Login Failure");
request.getRequestDispatcher(address).include(request,response);
This is how is get the value in the JSP file.
<% String error = (String)request.getAttribute("error") %>
I also tried it this way:
<% String error = (String)request.getParameter("error") %>
What could be the problem ?
Sam

[Craig Jackson]

Sam, I think you may have it backwards.
The

RequestDispatcher.include(ServletRequest req, ServletResponse res).include  

will include the content of the resource as apart of the ServletResponse, while the

RequestDispatcher.forward(ServletRequest req, ServletResponse res)  

will forward the request from a servlet to another resource.
I hope this helps.
Craig.

[himanshu patel]

Originally posted by Sam Maivia:
I am trying to a pass a value from a servlet to a jsp. I am getting null pointer exception. Error 503 Service Unavailable.
In the servlets file I send the values as:
request.setAttribute("error", "Login Failure");
request.getRequestDispatcher(address).include(request,response);
This is how is get the value in the JSP file.
<% String error = (String)request.getAttribute("error") %>
I also tried it this way:
<% String error = (String)request.getParameter("error") %>
What could be the problem ?
Sam

Try with
request.getRequestDispatcher(address).forward(request,response);

[Pravin Panicker]

I think you want to include the jsp in this servlet.. in which case the procedure you are following is correct.
Please clarify
1. What is the "address" you are giving to requestdispatcher. If it is absolute or relative.
2. Are you changing the response header in the included jsp page?

[Pravin Panicker]

request.setAttribute("error", "Login Failure");
request.getRequestDispatcher(address).include(request,response);
This is how is get the value in the JSP file.
<% String error = (String)request.getAttribute("error") %>
I also tried it this way:
<% String error = (String)request.getParameter("error") %>

try this rather..
<jsp:include page="address" >
<jsp aram name="error" value="Login Failure"/>
</jsp:include>
use get parameter from the jsp....