Simple RPC framework

Message is the base class of RPC messages, and all RPC messages inherit from this class to implement their own OnCall calls.

ExecutorService is an RPC server that usually only needs to start a new thread.

Caller is an RPC client that provides 2 RPC methods, one is cast and one is call.

Refer examples

1. RPC server and client:

   RPC Message, RPC Server and RPC Client