Dubbo(2)发布Dubbo服务

主要参考Dubbo源码包里面的dubbo-demo源码；

1.项目结构：

2.pom.xml中的依赖：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.cy</groupId>
  <artifactId>dubbo-provider</artifactId>
  <version>0.0.1-SNAPSHOT</version>

  <dependencies>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>dubbo</artifactId>
            <version>2.6.0</version>
        </dependency>
        <dependency>
            <groupId>com.101tec</groupId>
            <artifactId>zkclient</artifactId>
            <version>0.10</version>
        </dependency>
        <dependency>
            <groupId>org.apache.curator</groupId>
            <artifactId>curator-framework</artifactId>
            <version>4.0.1</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.46</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.25</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>
        <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-all</artifactId>
            <version>4.0.35.Final</version>
        </dependency>
    </dependencies>

</project>

3.服务提供者接口：DemoProviderService:

package com.cy.service;

/**
 * 服务提供者接口
 * @author CY
 *
 */
public interface DemoProviderService {

    String sayHello(String name);
}

4.服务提供者接口实现类：DemoProviderServiceImpl:

package com.cy.service.impl;

import com.cy.service.DemoProviderService;

/**
 * 服务提供者接口实现类
 * @author CY
 *
 */
public class DemoProviderServiceImpl implements DemoProviderService {

    public String sayHello(String name) {
        return "Hello," + name;
    }

}

5.dubbo配置文件：dubbo-provider.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:dubbo="http://code.alibabatech.com/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-2.5.xsd
       http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">

    <!-- 提供方应用名称，用于计算依赖关系 -->
    <dubbo:application name="demo-provider"/>

    <!-- 使用zookeeper注册中心暴露服务地址 -->
    <dubbo:registry address="zookeeper://127.0.0.1:2181"/>

    <!-- 使用dubbo协议，在20880端口暴露服务 -->
    <dubbo:protocol name="dubbo" port="20880"/>

    <!-- service实现类作为本地的一个bean -->
    <bean id="demoProviderService" class="com.cy.service.impl.DemoProviderServiceImpl"/>

    <!-- 声明需要暴露的服务接口 -->
    <dubbo:service interface="com.cy.service.DemoProviderService" ref="demoProviderService"/>

</beans>

6.测试类：ProviderTest:

import java.io.IOException;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class ProviderTest {

    public static void main(String[] args) {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"dubbo-provider.xml"});
        context.start();
        System.out.println("服务提供者向zookeeper注册中心注册服务成功（端口：20880）");
        try {
            System.in.read();        // press any key to exit
        } catch (IOException e) {
            e.printStackTrace();
        }
        context.close();
    }
}

7.测试：

先启动zookeeper服务，运行zkServer.cmd;

在运行ProviderTest.java,console打印：

log4j:WARN No appenders could be found for logger (org.springframework.core.env.StandardEnvironment).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
服务提供者向zookeeper注册中心注册服务成功（端口：20880）

可以看到zkServer的命令窗口打印：

2018-09-16 11:12:57,314 [myid:] - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:NIOServerCnxnFactory@215] - Accepted
socket connection from /127.0.0.1:59894
2018-09-16 11:12:57,321 [myid:] - INFO  [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:2181:ZooKeeperServer@938] - Client attempt
ing to establish new session at /127.0.0.1:59894
2018-09-16 11:12:57,376 [myid:] - INFO  [SyncThread:0:ZooKeeperServer@683] - Established session 0x1000786f7320000 with
negotiated timeout 30000 for client /127.0.0.1:59894
2018-09-16 11:12:57,424 [myid:] - INFO  [ProcessThread(sid:0 cport:2181)::PrepRequestProcessor@653] - Got user-level Kee
perException when processing sessionid:0x1000786f7320000 type:create cxid:0x4 zxid:0xa txntype:-1 reqpath:n/a Error Path
:/dubbo/com.cy.service.DemoProviderService/configurators Error:KeeperErrorCode = NodeExists for /dubbo/com.cy.service.De
moProviderService/configurators

zookeeper接受了59894端口程序的链接：

C:\Users\CY>netstat -aon | findstr "59894"
TCP 127.0.0.1:2181 127.0.0.1:59894 ESTABLISHED 9192    正是test虚拟机java.exe程序；