Why would “java.lang.IllegalStateException: The resource configuration is not modifiable in this context.” appear deploying Jersey app?

Question

I have created an app implementing REST services locally using:

Eclipse Indigo Jersey 2.4 Tomcat 7.0.47

When running locally using Eclipse, the services work

Answer 1

Posting very late for anyone that stumbles across this problem. I had the exact same problem - worked locally in eclipse, but when I tried to deploy outside of Eclipse, it crashed and burned with the same stack trace in the question. The problem was due to double deployment of our webapps due to improper naming of the war files we were deploying.

When autoDeploy is set to true, tomcat expects a VERY specific naming convention of .war files that is related to the context path. For example, the context path “/foo/bar” must have a corresponding .war file named “foo#bar.war”. Additionally, a context path mapped to “/” or “” expects a war file called ROOT.war.

The complete naming rules can be found here: http://tomcat.apache.org/tomcat-7.0-doc/config/context.html#Naming

Fixing the names of the war files solved the problem.

I also want to note that, eventually, eclipse also choked on the issue for me. Occasionally, doing a clean of the project and trying to re-run will fix the problem, but not every time, and I'm not sure why it fixes it. I'm still trying to find a complete solution. Solving the problem for eclipse is a bit harder because (as far as I know) I can't specify the name of the directory where eclipse publishes the project. For example, a project in eclipse named "foo" whose context root is "bar/baz" will be published in a directory named "foo" rather than "bar#baz" and tomcat/Jersey does not seem to like that.

I hope this helps save someone the 12+ hours it took me and my team to debug this problem the night before a demo :)