http://www.gwtproject.org/doc/latest/tutorial/RPC.html
http://www.gwtproject.org/doc/latest/DevGuideServerCommunication.html
    ServiceDefTarget ??? for binding

http://www.gwtproject.org/doc/latest/DevGuideCodingBasicsDeferred.html

https://www.tutorialspoint.com/gwt/gwt_rpc_communication.htm

protocol:
https://docs.google.com/document/d/1eG0YocsYYbNAtivkLtcaiEE5IOF5u4LUol8-LL0TIKU/edit

Service:
http://www.gwtproject.org/javadoc/latest/com/google/gwt/user/client/rpc/RemoteService.html

Servlet:
http://www.gwtproject.org/javadoc/latest/com/google/gwt/user/server/rpc/RemoteServiceServlet.html

RpcRequestBuilder:
http://www.gwtproject.org/javadoc/latest/com/google/gwt/user/client/rpc/RpcRequestBuilder.html
http://www.programcreek.com/java-api-examples/index.php?api=com.google.gwt.user.client.rpc.RpcRequestBuilder

format:
http://stackoverflow.com/questions/6135590/gwt-rpc-data-format

https://docs.google.com/document/d/1eG0YocsYYbNAtivkLtcaiEE5IOF5u4LUol8-LL0TIKU/edit

http://blog.daniel-kurka.de/2016/07/gwt-rpcs-future.html
https://dzone.com/articles/making-gwt-remote-procedure-ca
http://blog.gdssecurity.com/labs/2009/10/8/gwt-rpc-in-a-nutshell.html
http://www.techhui.com/profiles/blogs/simpler-and-speedier-gwt-with