Spring Web Service

http://static.springsource.org/spring-ws/sites/2.0/reference/html/why-contract-first.html

Remote Procedure Calls (RPC) is an integration style that tries to hide the fact that different
services are running on different systems. The method invocation is serialized
over the network to the service provider, where the service is invoked. The return
value is then serialized and sent back to the invoker.