Method invoke

stub/src/main/java/io/grpc/stub/ServerCalls.java:315–315

The provided responseObserver will extend ServerCallStreamObserver.

(ReqT request, StreamObserver<RespT> responseObserver)

     * The provided {@code responseObserver} will extend {@link ServerCallStreamObserver}.
     */
    void invoke(ReqT request, StreamObserver<RespT> responseObserver);
  }

  private interface StreamingRequestMethod<ReqT, RespT> {