Java: JSP halt execution on rest of page
- by bguiz
Hi,
How do you stop a JSP from executing?
I have JSPs which kick the user off a page by means of a "forward".
public boolean kickIfNotLoggedIn(
HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException {
//code to check if user is logged in
req.getRequestDispatcher(
ACCESS_DENIED_PAGE).forward(request, response);
}
In my JSP, I have this code, BEFORE any HTML output:
<%
//loginHelper.kickIfNotLoggedIn(request, response);
if (!loginHelper.kickIfNotLoggedIn(request, response)) {
return;
}
%>
If I don't use the return statement, the JSP continues processing, and I get a NullPointerException. If I use the return statement (as is commonly suggested on various sources on the net), I get an IllegalStateException:
StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception
java.lang.IllegalStateException: PWC3991: getOutputStream() has already been called for this response
at org.apache.coyote.tomcat5.CoyoteResponse.getWriter(CoyoteResponse.java:717)
at org.apache.coyote.tomcat5.CoyoteResponseFacade.getWriter(CoyoteResponseFacade.java:226)
at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:187)
Any ideas how to fix this, or another way to achieve an access denied page?
Thanks
