| /*
|
| * Copyright 1999-2011 Alibaba Group.
|
| *
|
| * Licensed under the Apache License, Version 2.0 (the "License");
|
| * you may not use this file except in compliance with the License.
|
| * You may obtain a copy of the License at
|
| *
|
| * http://www.apache.org/licenses/LICENSE-2.0
|
| *
|
| * Unless required by applicable law or agreed to in writing, software
|
| * distributed under the License is distributed on an "AS IS" BASIS,
|
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
| * See the License for the specific language governing permissions and
|
| * limitations under the License.
|
| */
|
| package com.alibaba.dubbo.rpc; |
| |
| import com.alibaba.dubbo.common.URL;
|
| import com.alibaba.dubbo.common.extension.Adaptive;
|
| import com.alibaba.dubbo.common.extension.SPI;
|
| |
| /** |
| * Protocol. (API/SPI, Singleton, ThreadSafe) |
| * |
| * @author william.liangf |
| */
|
| @SPI("dubbo") |
| public interface Protocol { |
| |
| /** |
| * 获取缺省端口,当用户没有配置端口时使用。 |
| * |
| * @return 缺省端口 |
| */ |
| int getDefaultPort(); |
|
|
| /**
|
| * 暴露远程服务:<br>
|
| * 1. 协议在接收请求时,应记录请求来源方地址信息:RpcContext.getContext().setRemoteAddress();<br>
|
| * 2. export()必须是幂等的,也就是暴露同一个URL的Invoker两次,和暴露一次没有区别。<br>
|
| * 3. export()传入的Invoker由框架实现并传入,协议不需要关心。<br>
|
| *
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| * @param <T> 服务的类型
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| * @param invoker 服务的执行体
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| * @return exporter 暴露服务的引用,用于取消暴露
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| * @throws RpcException 当暴露服务出错时抛出,比如端口已占用
|
| */
|
| @Adaptive
|
| <T> Exporter<T> export(Invoker<T> invoker) throws RpcException;
|
|
|
| /**
|
| * 引用远程服务:<br>
|
| * 1. 当用户调用refer()所返回的Invoker对象的invoke()方法时,协议需相应执行同URL远端export()传入的Invoker对象的invoke()方法。<br>
|
| * 2. refer()返回的Invoker由协议实现,协议通常需要在此Invoker中发送远程请求。<br>
|
| * 3. 当url中有设置check=false时,连接失败不能抛出异常,并内部自动恢复。<br>
|
| *
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| * @param <T> 服务的类型
|
| * @param type 服务的类型
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| * @param url 远程服务的URL地址
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| * @return invoker 服务的本地代理
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| * @throws RpcException 当连接服务提供方失败时抛出
|
| */
|
| @Adaptive
|
| <T> Invoker<T> refer(Class<T> type, URL url) throws RpcException;
|
| |
| /**
|
| * 释放协议:<br>
|
| * 1. 取消该协议所有已经暴露和引用的服务。<br> |
| * 2. 释放协议所占用的所有资源,比如连接和端口。<br>
|
| * 3. 协议在释放后,依然能暴露和引用新的服务。<br> |
| */ |
| void destroy(); |
| |
| } |