Dubbo 是阿里巴巴公司开源的一个高性能优秀的服务框架,使得应用可通过高性能的 RPC 实现服务的输出和输入功能,可以和
Spring
框架无缝集成。 主要核心部件:
- Remoting: 网络通信框架,实现了 sync-over-async 和 request-response 消息机制.
- RPC: (Remote Procedure Call Protocol远程过程调用协议), 一个远程过程调用的抽象,支持负载均衡、容灾和集群功能
- Registry: 服务目录框架用于服务的注册和服务事件发布和订阅
Dubbo工作原理
- Provider
- 暴露服务方称之为“服务提供者”。
- Consumer
- 调用远程服务方称之为“服务消费者”。
- Registry
- 服务注册与发现的中心目录服务称之为“服务注册中心”。
- Monitor
- 统计服务的调用次调和调用时间的日志服务称之为“服务监控中心”。
例子 服务端
定义一个Service Interface:( HelloService.java )
package com.alibaba.hello.api;
public interface HelloService{String sayHello(String name);
}
接口的实现类:( HelloServiceImpl.java )
package com.alibaba.hello.impl;
import com.alibaba.hello.api.HelloService;
public class HelloServiceImpl implements HelloService{public String sayHello(String name){return "Hello " + name;}
}
Spring配置:( provider.xml )<?xml version="1.0" encoding="UTF-8"?> <beans ......><!-- Application name --><dubbo:application name="hello-world-app" /><!-- registry address, used for service to register itself --><dubbo:registry address="multicast://224.5.6.7:1234" /><!-- expose this service through dubbo protocol, through port 2 0 8 8 0 --><dubbo:protocol name="dubbo" port="2 0 8 8 0" /><!-- which service interface do we expose? --><dubbo:service interface="com.alibaba.hello.api.HelloService" ref="helloService" /><!-- designate implementation --><bean id="helloService" class="com.alibaba.hello.impl.HelloServiceImpl" /> </beans>测试代码:( Provider.java )
import org.springframework.context.support.ClassPathXmlApplicationContext; public class Provider { public static void main(String[] args) {ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[] {"provider.xml"}); //启动成功,监听端口为2 0 8 8 0System.in.read(); // 按任意键退出} }客户端
Spring配置文件:( consumer.xml )
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns=......> <!-- consumer application name --> <dubbo:application name="consumer-of-helloworld-app" /> <!-- registry address, used for consumer to discover services --> <dubbo:registry address="multicast://224.5.6.7:1234" /> <!-- which service to consume? --> <dubbo:reference id="helloService" interface="com.alibaba.hello.api.HelloService" /> </beans>客户端测试代码:( Consumer.java )
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.alibaba.hello.api.HelloService; public class Consumer {public static void main(String[] args) {ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[] {"consumer.xml"});HelloService helloService = (HelloService)context.getBean("helloService"); // get service invocation proxyString hello = helloService.sayHello("world"); // do invoke!System.out.println( hello ); // cool, how are you~} }