Interface RpcChannel (3.19.4)

public interface RpcChannel

Abstract interface for an RPC channel. An RpcChannel represents a communication line to a Service which can be used to call that Service's methods. The Service may be running on another machine. Normally, you should not call an RpcChannel directly, but instead construct a stub Service wrapping it. Example:

RpcChannel channel = rpcImpl.newChannel("remotehost.example.com:1234"); RpcController controller = rpcImpl.newController(); MyService service = MyService.newStub(channel); service.myMethod(controller, request, callback);

Starting with version 2.3.0, RPC implementations should not try to build on this, but should instead provide code generator plugins which generate code specific to the particular RPC implementation. This way the generated code can be more appropriate for the implementation in use and can avoid unnecessary layers of indirection.

public abstract void callMethod(Descriptors.MethodDescriptor method, RpcController controller, Message request, Message responsePrototype, RpcCallback<Message> done)

Call the given method of the remote service. This method is similar to Service.callMethod() with one important difference: the caller decides the types of the Message objects, not the callee. The request may be of any type as long as request.getDescriptor()

method.getInputType()

. The response passed to the callback will be of the same type as responsePrototype (which must have getDescriptor() method.getOutputType()).