HELP! Exception Processing ErrorPage

[Robert Paris]

I am getting a weird error and I'm not sure why. I have an error page set which contains the following:

<%@ page isErrorPage="true" %>
<%
if ( exception != null )
{
System.out.println( exception.getMessage() ); 
}
else
{
%> 
     Found Nothing
<%
}

It keeps throwing an exception (as I see in the log messages) of type java.lang.IllegalStateException. It says: "Exception Processing ErrorPage"
This error even happens when I try to go to a page that doesn't exist (i.e. a 404) so I know it's not because of me trying to mess with the response. And I get the error even if I take all code out of my error page!
Any ideas?
[ January 06, 2004: Message edited by: Robert Paris ]

[Bear Bibeault]

Is it perhaps the "response already comitted" exception?
bear

[Robert Paris]

I don't see how since it throws this exception even on a 404 error. Why does it throw a "committed" error? What can I do to fix this? It's even doing it on a 404!
Here's the full error:

2004-01-06 14:18:14 ErrorDispatcherValve[localhost]: Exception Processing ErrorPage[exceptionType=java.lang.Exception, location=/errorHandler.jsp]
java.lang.IllegalStateException
at org.apache.coyote.Response.reset(Response.java:335)
at org.apache.coyote.tomcat4.CoyoteResponse.reset(CoyoteResponse.java:642)
at org.apache.coyote.tomcat4.CoyoteResponse.reset(CoyoteResponse.java:838)
at org.apache.catalina.valves.ErrorDispatcherValve.custom(ErrorDispatcherValve.java:413)
at org.apache.catalina.valves.ErrorDispatcherValve.throwable(ErrorDispatcherValve.java:258)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:179)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:172)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:641)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline$StandardPipelineValveContext.invokeNext(StandardPipeline.java:643)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:480)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:995)
at org.apache.coyote.tomcat4.CoyoteAdapter.service(CoyoteAdapter.java:223)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:594)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:392)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:565)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:619)
at java.lang.Thread.run(Thread.java:536)

[ January 06, 2004: Message edited by: Robert Paris ]

[Robert Paris]

OK, did some more testing and here's something weird:
If I set errorPage="errorHandler.jsp" in my web page that's throwing an error, then it includes the error page output. However, 404 errors still don't work! Please, someone help me!

[Robert Paris]

OK, still got a problem but it gets more interesting. I was using Tomcat 4.1.24. When I switched to Tomcat 4.1.29 the 404 problem went away. Now on a 404 error, it displays my errorHandler.jsp page.
Unfortunately, when I throw an exception in my JSP page it still cannot go to my errorHandler.jsp page - it still throws the IllegalStateException. It's because the exception gets thrown part-way down the page so I guess the response has some data already written - is there a way to change that? And why does the spec allow setting an error-handling page via the web.xml descriptor for JSP pages if it won't work?!