Tomcat – Manually reload Webbapplication without Tomcat Manager possible

Tomcat does not use the CLASSPATH in the webapp's classloader. You can add paths and files to the common.loader line in conf/catalina.properties. The classloader should have found the class when the jar was in WEB-INF/lib. I can't explain why it hasn't. If you are using 5.5, you can place the jar in common/lib or lib/ if you're using tomcat6. This path is loaded by a higher level classloader and should be picked up first.

The MaxFileSize will be calculated after the whole file has been already uploaded. You can upload a file (1GB size) on your web app, then you will notice what really happen. So relying on the Tomcat would make no sense. Doing same work in Servlet is possible, but when your counter reaches the MaxFileSize how you can disconnect the underlying HTTP connection? I think you have no way. The HTTP protocol is unidirectional, so you can't also tell browser to cancel the long post in time. The only thing you can do is when your counter reaches the threshold just ignore the follow-up bytes from input stream to protect disk space till the file transmission complete.