awesome-java

Out of those two choices, Java easily wins. The open source tools & libraries for it make .NET's pale in comparison. Regarding frameworks/strategy, I'd recommend you try to go vanilla java for as long as possible and stay away from all the frameworks you mentioned, like JSF, Spring Boot, Hibernate, JBoss, etc. Because dependencies. AFAIK, none of the ones you mentioned offer a really compelling value proposition, but they will all bring along their constraints. That is unless they you have some really specific requirement in mind to justify adopting one of them. For general stuff like REST or M2M you might want to look at DropWizard or grpc. If you want to go shopping for replacement libs, here is a list of some general libs that someone made: https://github.com/akullpp/awesome-java You could also try doing a general search on github.