JAVA中几种常用的RPC框架介绍

1. 浅谈服务治理与微服务 http://blog.csdn.net/suifeng3051/article/details/53992560

2. RPC框架可以从语言兼容和服务治理不同角度来划分：

从语言兼容上的rpc框架有 thrift zeroC-ICE protbuf

从服务治理角度的rpc架构有 dubbo RMI、Hessian spring Cloud

 

 

所谓服务治理，主要包括服务发现、负载均衡、容错、日志收集等功能

1.dubbo：

 使用Hessian的序列化协议，传输则是TCP协议，使用了高性能的NIO框架Netty

 

服务接口

 public interface DemoService { 2 String sayHello(String name); 3 } 

服务实现

public class DemoServiceImpl implements DemoService {
    public String sayHello(String name) {
        return "Hello " + name;
    }
}

Configure service provider

The code snippet below shows how a dubbo service provider is configured with spring framework, which is recommended, however you could also use API configuration if it’s preferred.

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
    <dubbo:application name="demo-provider"/>
    <dubbo:registry address="multicast://224.5.6.7:1234"/>
    <dubbo:protocol name="dubbo" port="20880"/>
    <dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoService"/>
    <bean id="demoService" class="com.alibaba.dubbo.demo.provider.DemoServiceImpl"/>
</beans>

Start service provider

public class Provider {
    public static void main(String[] args) throws Exception {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
                new String[] {"META-INF/spring/dubbo-demo-provider.xml"});
        context.start();
        System.in.read(); // press any key to exit
    }
}

Configure service consumer

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/schema/dubbo"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">
    <dubbo:application name="demo-consumer"/>
    <dubbo:registry address="multicast://224.5.6.7:1234"/>
    <dubbo:reference id="demoService" interface="com.alibaba.dubbo.demo.DemoService"/>
</beans>

Run service consumer

public class Consumer {
    public static void main(String[] args) throws Exception {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
                new String[]{"META-INF/spring/dubbo-demo-consumer.xml"});
        context.start();
        DemoService demoService = (DemoService) context.getBean("demoService"); // obtain proxy object for remote invocation
        String hello = demoService.sayHello("world"); // execute remote invocation
        System.out.println(hello); // show the result
    }
}

 

2.RMI

• 　　 实现结构图

 

对外接口：

public interface IService extends Remote {  
       
         public String queryName(String no) throws RemoteException;  
       
     }

接口实现

public class ServiceImpl extends UnicastRemoteObject implements IService {

    @Override
    public String queryName(String no) throws RemoteException {
        // 方法的具体实现
        System.out.println("hello" + no);
        return String.valueOf(System.currentTimeMillis());
    }

// RMI客户端
public class Client {

    public static void main(String[] args) {
        // 注册管理器
        Registry registry = null;
        try {
            // 获取服务注册管理器
            registry = LocateRegistry.getRegistry("127.0.0.1",8088);
            // 列出所有注册的服务
            String[] list = registry.list();
            for(String s : list){
                System.out.println(s);
            }
        } catch (RemoteException e) {
            
        }
        try {
            // 根据命名获取服务
            IService server = (IService) registry.lookup("vince");
            // 调用远程方法
            String result = server.queryName("ha ha ha ha");
            // 输出调用结果
            System.out.println("result from remote : " + result);
        }32     }
}

 

// RMI服务端
public class Server {

    public static void main(String[] args) {
        // 注册管理器
        Registry registry = null;
            // 创建一个服务注册管理器
            registry = LocateRegistry.createRegistry(8088);
            // 创建一个服务
            ServiceImpl server = new ServiceImpl();
            // 将服务绑定命名
            registry.rebind("vince", server);
 23         }
    }
}

3.Hessian

基于HTTP的远程方法调用，在性能方面还不够完美，负载均衡和失效转移依赖于应用的负载均衡器，Hessian的使用则与RMI类似，区别在于淡化了Registry的角色，通过显示的地址调用，利用HessianProxyFactory根据配置的地址create一个代理对象，另外还要引入Hessian的Jar包。