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

In my case, I had a Jersey POST resource for file uploads. The resource specified the parameter: @FormDataParam("file") InputStream file

and consumed MediaType.MULTIPART_FORM_DATA.

To fix the issue, I had to add the following to the Jersey REST configuration in my web.xml file:

    jersey.config.server.provider.classnames
    org.glassfish.jersey.media.multipart.MultiPartFeature