I don't think the problem is Java documentation/community support.

It's really that with the exception of Play/Grails/Vert.x the frameworks are horrifically over-engineered by developers who live and breathe in the enterprise space. Nobody has ever really cared much about smaller, more startup land developers. So Java has required so much knowledge and involvement just to do the simplest things.

I would take a look at frameworks like Play for the future of the platform.