Dubbo远程调用服务框架原理与示例 - 沐风山

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~}
}