Spring Web Socket Java Client

Spring 4.1 introduces a SockJs Java Client which is quite useful for server to server communication and performance testing. It doesn't come with a Stomp client (this is certainly in the roadmap) but you can check out the tests in the sample app which has already an implementation. Seems this is what you are looking for.

Update 8 Sep 2015:

Spring 4.2 has a STOMP Java client which can be used along with the SockJS Java client. More: https://docs.spring.io/spring/docs/4.2.x/spring-framework-reference/htmlsingle/#websocket-stomp-client