dubbo的demo中的provider实现很简单，

1.接口如下：

package com.alibaba.dubbo.demo;public interface DemoService {    String sayHello(String name);}

2.实现类：

package com.alibaba.dubbo.demo.provider;import com.alibaba.dubbo.demo.DemoService;import com.alibaba.dubbo.rpc.RpcContext;import java.text.SimpleDateFormat;import java.util.Date;public class DemoServiceImpl implements DemoService {    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 form provider: " + RpcContext.getContext().getLocalAddress();    }}

3.主要配置文件dubbo-demo-provider.xml内容如下：

4.main类：

import org.springframework.context.support.ClassPathXmlApplicationContext;public class Provider {    public static void main(String[] args) throws Exception {        //Prevent to get IPV6 address,this way only work in debug mode        //But you can pass use -Djava.net.preferIPv4Stack=true,then it work well whether in debug mode or not        System.setProperty("java.net.preferIPv4Stack", "true");        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbo-demo-provider.xml"});        context.start();        System.in.read(); // press any key to exit    }}

5.那么dubbo配置文件的解析是怎么解决的呢？是什么时候开始的呢？

1）在源码的dubbo-config下的dubo-config-spring中的META-INF下面有两个文件：

spring.schemas和spring.handlers

spring.schemas内容为：http\://code.alibabatech.com/schema/dubbo/dubbo.xsd=META-INF/dubbo.xsd

解说：dubbo.xsd是dubbo在spring中可以使用的元素的定义，如protocol，registry等

spring.handlers内容为：

http\://code.alibabatech.com/schema/dubbo=com.alibaba.dubbo.config.spring.schema.DubboNamespaceHandler

解说：DubboNamespaceHandler是注册dubbo中用到的各个元素的解析类，它的源码内容如下：

public class DubboNamespaceHandler extends NamespaceHandlerSupport {    static {        Version.checkDuplicate(DubboNamespaceHandler.class);    }    public void init() {        registerBeanDefinitionParser("application", new DubboBeanDefinitionParser(ApplicationConfig.class, true));        registerBeanDefinitionParser("module", new DubboBeanDefinitionParser(ModuleConfig.class, true));        registerBeanDefinitionParser("registry", new DubboBeanDefinitionParser(RegistryConfig.class, true));        registerBeanDefinitionParser("monitor", new DubboBeanDefinitionParser(MonitorConfig.class, true));        registerBeanDefinitionParser("provider", new DubboBeanDefinitionParser(ProviderConfig.class, true));        registerBeanDefinitionParser("consumer", new DubboBeanDefinitionParser(ConsumerConfig.class, true));        registerBeanDefinitionParser("protocol", new DubboBeanDefinitionParser(ProtocolConfig.class, true));        registerBeanDefinitionParser("service", new DubboBeanDefinitionParser(ServiceBean.class, true));        registerBeanDefinitionParser("reference", new DubboBeanDefinitionParser(ReferenceBean.class, false));        registerBeanDefinitionParser("annotation", new DubboBeanDefinitionParser(AnnotationBean.class, true));    }

而DubboBeanDefinitionParser是具体解析的类，解析dubbo-demo-provider.xml中的配置，并封装相关的bean.

从而进行服务启动的一些准备，包括服务export,注册等。

2）什么开始的，通过下面的截图可以一目了然：

注：1）dubbo的源码地址：

2）spring schema的学习请看以下链接：