Allow a WorkerImpl subclass to validate the jobType

[michaelcameron]

The Grails Jesque plugin cannot use Jesque 1.3.0 out of the box because of issue 24 (michaelcameron/grails-jesque#24). In short, I had to override the addJobType early on just to loosen the requirement that the jobType class is Runnable or Callable so the job types can just be POGOs and we can follow convention over configuration.

With changes in Jesque 1.3.0 the constructor changed from adding jobTypes directly to the JobType map to calling addJobType. This started a cascade of code that leads to the GrailsWorkerImpl trying to add directly to the jobType map. I think it turns out my implementation of addJobType would never have worked, because it would have received the unmodifiable version returned by WorkerImpl.getJobTypes, but in all cases the jobTypes were set in the constructor (and thus worked in jesque < 1.3.0).

[gresrun]

I'll work on getting a 1.3.1 release out this evening for you.

[michaelcameron]

Thanks.

[gresrun]

Just cut the 1.3.1 release; should be up in Maven Central in a few hours.