1// Protocol Buffers - Google's data interchange format 2// Copyright 2008 Google Inc. All rights reserved. 3// http://code.google.com/p/protobuf/ 4// 5// Redistribution and use in source and binary forms, with or without 6// modification, are permitted provided that the following conditions are 7// met: 8// 9// * Redistributions of source code must retain the above copyright 10// notice, this list of conditions and the following disclaimer. 11// * Redistributions in binary form must reproduce the above 12// copyright notice, this list of conditions and the following disclaimer 13// in the documentation and/or other materials provided with the 14// distribution. 15// * Neither the name of Google Inc. nor the names of its 16// contributors may be used to endorse or promote products derived from 17// this software without specific prior written permission. 18// 19// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 29// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 31package com.google.protobuf; 32 33/** 34 * <p>Abstract interface for an RPC channel. An {@code RpcChannel} represents a 35 * communication line to a {@link Service} which can be used to call that 36 * {@link Service}'s methods. The {@link Service} may be running on another 37 * machine. Normally, you should not call an {@code RpcChannel} directly, but 38 * instead construct a stub {@link Service} wrapping it. Example: 39 * 40 * <pre> 41 * RpcChannel channel = rpcImpl.newChannel("remotehost.example.com:1234"); 42 * RpcController controller = rpcImpl.newController(); 43 * MyService service = MyService.newStub(channel); 44 * service.myMethod(controller, request, callback); 45 * </pre> 46 * 47 * <p>Starting with version 2.3.0, RPC implementations should not try to build 48 * on this, but should instead provide code generator plugins which generate 49 * code specific to the particular RPC implementation. This way the generated 50 * code can be more appropriate for the implementation in use and can avoid 51 * unnecessary layers of indirection. 52 * 53 * @author kenton@google.com Kenton Varda 54 */ 55public interface RpcChannel { 56 /** 57 * Call the given method of the remote service. This method is similar to 58 * {@code Service.callMethod()} with one important difference: the caller 59 * decides the types of the {@code Message} objects, not the callee. The 60 * request may be of any type as long as 61 * {@code request.getDescriptor() == method.getInputType()}. 62 * The response passed to the callback will be of the same type as 63 * {@code responsePrototype} (which must have 64 * {@code getDescriptor() == method.getOutputType()}). 65 */ 66 void callMethod(Descriptors.MethodDescriptor method, 67 RpcController controller, 68 Message request, 69 Message responsePrototype, 70 RpcCallback<Message> done); 71} 72