This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
I would be a bit concerned that you are trying to implement security through obscurity but the key is to have your web application set up correctly. In the event of an error your web app needs to have the web.xml set up. For example:
This tells Tomcat to redirect to /500.html in the event of a 500 error (the most common error when you have an issue with your JSP).
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