Eclipse, Maven and Annotation Processing

Most of the time, I'm fine with the built-in Java compiler of Eclipse, but in some edge cases it doesn't cut it, and I want my javac back. One of these cases is to run tests using an annotation processor that the Eclipse JDT compiler won't pick up as per default. As I spend most of my time in projects using Maven as the build tool, I could use the command line commands for Surefire to run a single test class like so:

mvn -Dtest=TestCircle test

As Surefire will strip off any file extension that happens to be there, it's quite easy to create an External Tools Configuration that generates the right command. Here's my configuration for running a single test class:

You'll probably want to have it in your favorites menu as well, that setting is on the Common tab. Also make sure to allocate a Console for the output (on the Common tab as well). Linking the source editor to Package Explorer makes it really convenient to execute the test you're working on.

The other way around would be to fix the real problem, and configure Annotation Processing in Eclipse. Here you need to turn on annotation processing for the project and add the jar files where the annotation processors live. To handle changes in a sane way, I used a variable for the needed jar file:

When it works this approach gives full integration into Eclipse JDT which I like. Unfortunately it seems to be quite brittle. I had it working at one point, but then the annotation processing was lost again. I'd appreciate any comments pointing out how to make that work in a stable fashion!