下面是本文将介绍实例在IDEA开发环境的项目结构，该项目使用MAVEN进行编译打包和依赖管理。如下图：
上图中，dubbo-hello程序有3个子模块，分别为 dubbo-api（定义我们的服务接口）、dubbo-provider（服务接口的具体实现，也是我们要暴露出去的服务）和dubbo-consumer（服务消费者）。下面将分别对他们进行详细讲解。
注意：该实例是基于Zookeeper搭建，将Zookeeper作为Dubbo的注册中心。（如果不知道怎样安装Zookeeper，请查看《Zookeeper Windows单机安装》）
该模块是一个非常简单的maven项目，其中只有一个接口 HelloService.java。如下图：
HelloService.java代码如下：
package com.huangx.dubbo.hello;
/**
* 定义SOA服务的接口
*/
public interface HelloService {
/**
* 接口方法
* @param name
* @return
*/
String sayHello(String name);
}该模块是一个非常简单的maven项目，该模块依赖了dubbo-api模块。该模块的接口如下图：
其中：
HelloServiceImpl 实现了HelloService接口
Provider 为启动类
dubbo.properties
dubbo-demo-provider.xml dubbo的spring配置文件
log4j.properties 日志配置文件
HelloServiceImpl.java代码
package com.huangx.dubbo.provider;
import com.huangx.dubbo.hello.HelloService;
import com.alibaba.dubbo.rpc.RpcContext;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* 服务实现
*/
public class HelloServiceImpl implements HelloService {
public String sayHello(String name) {
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
System.out.println("[" + sdf.format(new Date()) + "] Hello " + name
+ ", request from consumer: "
+ RpcContext.getContext().getRemoteAddress());
return "Hello " + name + ", response from provider: "
+ RpcContext.getContext().getLocalAddress();
}
}Provider.java代码
package com.huangx.dubbo.provider;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* 加载 Spring 的配置文件，启动 Dubbo 服务提供者
*/
public class Provider {
public static void main(String[] args) throws Exception {
// 防止获取IPV6地址，这种方式只工作在debug模式下。
// 但是，你能通过 -Djava.net.preferIPv4Stack=true。
// 那么，debug或不是debug模式都能很好的工作。
System.setProperty("java.net.preferIPv4Stack", "true");
// 加载 Spring 配置文件，启动 Dubbo
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
new String[] {"dubbo-demo-provider.xml"});
context.start();
// 按任意键退出
System.in.read();
context.close();
}
}dubbo.properties配置
dubbo.application.qos.port=22222
dubbo-demo-provider.xml配置文件
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="https://code.alibabatech.com/schema/dubbo" xmlns="https://www.springframework.org/schema/beans" xsi:schemaLocation="https://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans-4.3.xsd https://code.alibabatech.com/schema/dubbo https://code.alibabatech.com/schema/dubbo/dubbo.xsd"> <!-- 提供应用名称，用于计算依赖关系 --> <dubbo:application name="demo-provider"/> <!-- 使用多播注册中心导出服务 --> <!--<dubbo:registry address="multicast://224.0.0.100:1234"/>--> <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181" /> <!-- 使用 dubbo 协议在 20880 端口导出服务 --> <dubbo:protocol name="dubbo" port="20880"/> <!-- 服务实现，与常规本地bean相同 --> <bean id="demoService" class="com.huangx.dubbo.provider.HelloServiceImpl"/> <!-- 声明要导出的服务接口 --> <dubbo:service interface="com.huangx.dubbo.hello.HelloService" ref="demoService"/> </beans>
log4j.properties配置
###set log levels###
log4j.rootLogger=info, stdout
###output to the console###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%d{dd/MM/yy hh:mm:ss:sss z}] %t %5p %c{2}: %m%n该模块是一个非常简单的maven项目，该模块依赖了dubbo-api模块。该模块的接口如下图：
其中：
Consumer.java 为消费者
dubbo.properties
dubbo-demo-provider.xml dubbo的spring配置文件
log4j.properties 日志配置文件
Consumer.java代码
package com.huangx.dubbo.consumer;
import com.huangx.dubbo.hello.HelloService;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* 加载 Spring 配置，启动 Dubbo 服务消费者
*/
public class Consumer {
public static void main(String[] args) {
System.setProperty("java.net.preferIPv4Stack", "true");
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(
new String[] { "dubbo-demo-consumer.xml" });
context.start();
// 获取远程服务
HelloService demoService = (HelloService) context.getBean("demoService");
while (true) {
try {
Thread.sleep(1000);
// 调用远程方法
String hello = demoService.sayHello("word");
// 获取结果
System.out.println(hello);
} catch (Throwable throwable) {
throwable.printStackTrace();
}
}
}
}dubbo.properties配置
dubbo.application.qos.port=33333
dubbo-demo-consumer.xml配置文件
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="https://code.alibabatech.com/schema/dubbo" xmlns="https://www.springframework.org/schema/beans" xsi:schemaLocation="https://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans-4.3.xsd https://code.alibabatech.com/schema/dubbo https://code.alibabatech.com/schema/dubbo/dubbo.xsd"> <!-- 使用者的应用程序名称，用于计算应用间的依赖关系(不是匹配标准)， 不要设置与提供者相同的设置 --> <dubbo:application name="demo-consumer"/> <!-- 使用多播注册中心发现服务 --> <!--<dubbo:registry address="multicast://224.0.0.100:1234"/>--> <dubbo:registry protocol="zookeeper" address="127.0.0.1:2181" /> <!-- 生成远程服务的代理，然后可以像使用本地接口一样去使用demoService服务 --> <dubbo:reference id="demoService" check="false" interface="com.huangx.dubbo.hello.HelloService"/> </beans>
log4j.properties配置
###set log levels###
log4j.rootLogger=info, stdout
###output to console###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=[%d{dd/MM/yy hh:mm:ss:sss z}] %t %5p %c{2}: %m%n运行效果如下图：
provider
[23/03/19 08:24:17:017 CST] main INFO support.ClassPathXmlApplicationContext: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@7dc5e7b4: startup date [Sat Mar 23 08:24:17 CST 2019]; root of context hierarchy [23/03/19 08:24:17:017 CST] main INFO xml.XmlBeanDefinitionReader: Loading XML bean definitions from class path resource [dubbo-demo-provider.xml] [23/03/19 08:24:18:018 CST] main INFO logger.LoggerFactory: using logger: com.alibaba.dubbo.common.logger.log4j.Log4jLoggerAdapter [23/03/19 08:24:19:019 CST] main INFO config.AbstractConfig: [DUBBO] The service ready on spring started. service: com.huangx.dubbo.hello.HelloService, dubbo version: 2.5.3, current host: 127.0.0.1 [23/03/19 08:24:19:019 CST] main INFO config.AbstractConfig: [DUBBO] Export dubbo service com.huangx.dubbo.hello.HelloService to local registry, dubbo version: 2.5.3, current host: 127.0.0.1 ... [23/03/19 08:24:20:020 CST] ZkClient-EventThread-16-127.0.0.1:2181 INFO zkclient.ZkEventThread: Starting ZkClient event thread. [08:25:01] Hello word, request from consumer: /192.168.238.1:25229 [08:25:03] Hello word, request from consumer: /192.168.238.1:25229 [08:25:04] Hello word, request from consumer: /192.168.238.1:25229 ...
consumer
[23/03/19 08:24:48:048 CST] main INFO support.ClassPathXmlApplicationContext: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@7dc5e7b4: startup date [Sat Mar 23 08:24:48 CST 2019]; root of context hierarchy
[23/03/19 08:24:49:049 CST] main INFO xml.XmlBeanDefinitionReader: Loading XML bean definitions from class path resource [dubbo-demo-consumer.xml]
[23/03/19 08:24:50:050 CST] main INFO logger.LoggerFactory: using logger: com.alibaba.dubbo.common.logger.log4j.Log4jLoggerAdapter
[23/03/19 08:24:50:050 CST] main INFO zookeeper.ZookeeperRegistry: [DUBBO] Load registry store file C:\Users\Administrator\.dubbo\dubbo-registry-127.0.0.1.cache, data: {com.huangx.dubbo.hello.HelloService=empty://192.168.238.1:20880/com.huangx.dubbo.hello.HelloService?anyhost=true&application=demo-provider&category=configurators&check=false&dubbo=2.5.3&interface=com.huangx.dubbo.hello.HelloService&methods=sayHello&pid=12276&side=provider×tamp=1553300659717}, dubbo version: 2.5.3, current host: 127.0.0.1
[23/03/19 08:24:51:051 CST] ZkClient-EventThread-14-127.0.0.1:2181 INFO zkclient.ZkEventThread: Starting ZkClient event thread.
[23/03/19 08:25:00:000 CST] main INFO zookeeper.ZooKeeper: Client environment:zookeeper.version=3.3.3-1073969, built on 02/23/2011 22:27 GMT
[23/03/19 08:25:00:000 CST] main INFO zookeeper.ZooKeeper: Client environment:host.name=ZQCBUIB1T9KD4J6
[23/03/19 08:25:00:000 CST] main INFO zookeeper.ZooKeeper: Client environment:java.version=1.8.0_45
...
Hello word, response from provider: 192.168.238.1:20880
Hello word, response from provider: 192.168.238.1:20880提示：
在后续的Dubbo文章中均会使用到本文章附件的Dubbo基础环境。
