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Problems with Exception Handling via web.xml config

Mark Vedder
Ranch Hand

Joined: Dec 17, 2003
Posts: 624

Hello All,
I'm tying to configure a Web App to use specific Error pages for particular exceptions, but I am running into problems.
On Sun ONE Web Server v6.1 (Servlet 2.3 / JSP 1.2) I have the following web.xml:

com.foo.MySpecialException Extends java.sql.SQLException
A bean used by various JSP pages in the app can throw com.foo.MySpecialException
From my understanding, the container should use the most appropriate <error-page> entry to handle an exception. So when my Bean throws the com.foo.MySpecialException, the container should forward it to MySpecialException.jsp. Well it doesn't; it goes to the GeneralExceptions.jsp page (the planned catch all page). A on that page displays com.foo.MySpecialException: Message Details - so I know the container is �seeing� the proper exception type.
Now if I comment out the Throwable entry in the web.xml:

I get the MySpecialException.jsp - but this eliminates the ability to handle the unforeseen exceptions that the GeneralExceptions.jsp page was meant to handle.
What am I missing here? Why is the container not using the specified page?
A big thank you in advance for any and all Assistance
Frank Carver
Sheriff

Joined: Jan 07, 1999
Posts: 6920
My guess is that the JSP code is probably wrapping the actual thrown exception into a ServletException of some sort before it reaches your error pages. Try printing exception.getClass() in the catch-all JSP and seeing which class the exception really is.


Read about me at frankcarver.me ~ Raspberry Alpha Omega ~ Frank's Punchbarrel Blog
Mark Vedder
Ranch Hand

Joined: Dec 17, 2003
Posts: 624

Frank,
Thanks for the suggestion.
A <%= exception.getClass() %> is displaying class com.foo.MySpecialException
However, the container's error log does show:
[17/Dec/2003:13:59:11] failure ( 360): for host 127.0.0.1 trying to GET /dbgui/process.jsp, service-j2ee reports: StandardWrapperValve[jsp]: WEB2792: Servlet.service() for servlet jsp threw exception
javax.servlet.ServletException: My Bean's Specialized Message
<staack-trace>
...
----- Root Cause -----
com.foo.MySpecialException: My Bean's Specialized Message
<stack-trace>

Sorry that I missed that before. Any suggestions on how to work around this? I suppose I could catch the ServletException and then search the message string for key words to determine if I need to forward to the Special Error Page (or what error page to go to), but it seems like there should be an easier way (especially since I have different messages and they may change in the future - especially when the page is localized). Any suggestions.
Thanks
 
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