Hi,
I'm working on a Java-based wrapper for the REST API, to make it look more OO, abstracting the access to servers.
It uses methods such as
User bill = realm.getUser("bburke")
List<RoleRepresentation> roles = bill.getApplicationRoleMappings("customer-portal");
It's still in it's early stages, but if you find it interesting, I'd be happy to create a repo for other Java users to use it, and adapt it based on suggestions aswell.