catching exceptions tomcat servlet

i have set-up tomcat locate exceptions pass servlet following web.xml.

<servlet-mapping>
    <servlet-name>exception</servlet-name>
    <url-pattern>/exception</url-pattern>
</servlet-mapping>
<error-page>
    <exception-type>java.lang.exception</exception-type>
    <location>/exception</location>
</error-page>

this works glorious i have servlet logging information forwarding jsp. however i wish record uri caused difference thrown i request.getrequesturi() i /exception servlet route that's doing logging exception. i uncanny uri caused exception?