Question

Instead of using a certain jar in my WEB-INF/lib folder, I want to use its source code (same directory structure and everything) in my WEB-INF/classes folder, so that I may be able to modify its classes more story.

Yet (re)starting my tomcat after deleting the original jar and uploading the corresponding directory into WEB-INF/classes gives me the following error:

SEVERE: Error configuring application listener of class no.something.something1.http.LifecycleListener
java.lang.ClassNotFoundException: no.something.something1.http.LifecycleListener

I am certain that the directory path is the same as the one inside the jar. Also, I have previously tried using classes in my WEB-INF folder for this web application, and tomcat has also been unable to load them, for some reason.

Does anyone know how I go about troubleshooting this error?

Answer 1

Tomcat can only load .class files, it doesn’t know what to do with raw source code files. Tomcat doesn’t do hot loading of .class files like that anyway. You would have to restart the application or server after you recompiled them either way, packaging them as a .war isn’t that much of a burden either way once you automate it.

If you take the time to automate the build and deployment of a proper .war you can just rebuild the .war and it will automagically undeploy and redeploy the application itself, which is many times faster than restarting the entire server.

You can’t do what you are trying to do the way you are trying to do it. Tools like JRebel address these issues, but I don’t find them as useful as their marketing makes them sound.