I just found that org.jboss.resteasy.client.ClientRequest is deprecated, invalidating everything I could find on Google about how to use the RESTEasy client. The Javadoc gives no indication as to what to use instead. Google is likewise silent.
I have reverted to 2.3.5 for now, but would be interested in the answer anyways, as well as how one was supposed to find out the answer without asking someone else who knew – is there a resource with that information where I could have looked ?
The 3.0 beta documentation here describes these deprecations like so:
This would imply that the preferred method will be to use the JAX-RS Client API described in this post