Dubbo入门学习三—xml配置方式

在我看来Dubbo最为方便的还是通过Spring 容器来加载Dubbo的Bean配置。而最便捷的学习途径就是看官方文档和代码。这里贴出我的代码：NEZHA的GitHub代码仓库

这里主要分成三部分：

1. API
2. Provider
3. Consumer

1、API的设计

package com.nezha.demo.dubbo;

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

2、Provide的代码

1.api接口的实现类

package com.nezha.demo.dubbo;

import com.alibaba.dubbo.rpc.RpcContext;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DemoServiceImpl implements DemoService {
    @Override
    public String sayHello(String name) {
        System.out.println("[" + new SimpleDateFormat("HH:mm:ss").format(new Date()) + "] Hello " + name + ", request from consumer: " + RpcContext.getContext().getRemoteAddress());
        return "Hello " + name + ", response from provider: " + RpcContext.getContext().getLocalAddress();
    }
}

2.Dubbo的配置文件

文件位于resources包下面:/resources/spring/dubbo-demo-provider.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
       xmlns="http://www.springframework.org/schema/beans"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
       http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">

    <!-- provider's application name, used for tracing dependency relationship -->
    <dubbo:application name="demo-provider"/>

    <!-- use multicast registry center to export service -->
    <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181"/>

    <!-- use dubbo protocol to export service on port 20880 -->
    <dubbo:protocol name="dubbo" port="20880"/>

    <!-- service implementation, as same as regular local bean -->
    <bean id="demoService" class="com.nezha.demo.dubbo.DemoServiceImpl"/>

    <!-- declare the service interface to be exported -->
    <dubbo:service version="1.0.0" interface="com.nezha.demo.dubbo.DemoService" ref="demoService"/>

</beans>

3.Provider服务提供者

package com.nezha.demo.dubbo;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Provider {

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

3、Consumer的代码

1.Dubbo的xml配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
       xmlns="http://www.springframework.org/schema/beans"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
       http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">

    <!-- consumer's application name, used for tracing dependency relationship (not a matching criterion),
    don't set it same as provider -->
    <dubbo:application name="demo-consumer"/>

    <!-- use multicast registry center to discover service -->
    <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181"/>

    <!-- generate proxy for the remote service, then demoService can be used in the same way as the
    local regular interface -->
    <dubbo:reference scope="remote" version="1.0.0" id="demoService" check="false" interface="com.nezha.demo.dubbo.DemoService"/>

</beans>

2.Consumer的代码

package com.nezha.demo.dubbo;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Consumer {

    public static void main(String[] args) {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"spring/dubbo-demo-consumer.xml"});
        context.start();
        // get remote service proxy
        DemoService demoService = (DemoService) context.getBean("demoService");
        while (true) {
            try {
                Thread.sleep(1000);
                // call remote method
                String hello = demoService.sayHello("world");
                // get result
                System.out.println(hello);
            } catch (Throwable throwable) {
                throwable.printStackTrace();
            }
        }
    }
}