dubbo入门案例！！！

入门案例之前我们先介绍一下：zookeeper。

Zookeeper是Apacahe Hadoop的子项目，可以为分布式应用程序协调服务，适合作为Dubbo服务的注册中心，负责服务地址的注册与查找，相当于目录服务，服务提供者和消费者只在启动时与注册中心交互。

就不用安装了，我会上传一个安装包。

总结：

        1、什么是zookeeper？
                zookeeper：负责管理ip和port，是服务提供者和服务消费者的注册中心
        2、zookeeper的安装和启动
                安装：
                   解压即安装
                启动：
                    双击bin/zkServer.cmd

开始入门案例：（项目结构）

父工程的pom.xml

 <parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.3.2.RELEASE</version></parent>
<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- Dubbo Spring Boot Starter --><dependency><groupId>com.alibaba.boot</groupId><artifactId>dubbo-spring-boot-starter</artifactId><version>0.1.0</version></dependency><!-- 由于使⽤了zookeeper作为注册中⼼，则需要加⼊zookeeper的客户端jar包： --><dependency><groupId>com.101tec</groupId><artifactId>zkclient</artifactId><version>0.10</version></dependency></dependencies>

1、dobbo_interface模块

这个模块中我们就只写一个接口模拟一下就可以.

在com.by.service中写一个HelloService接口

/** Copyright (c) 2020, 2024,  All rights reserved.**/
package com.by.service;/*** <p>Project: dubbo_parent - HelloService</p>* <p>Powered by scl On 2024-01-17 13:56:01</p>* <p>描述：<p>** @author 孙臣龙 [[e-mail]]* @version 1.0* @since 17*/
public interface HelloService {String hello();
}

2、dobbo_provider模块

在这个模块中我们需要做：实现上个模块的接口，创建spring boot的启动类，创建配置类

pom.xml:

<dependencies><dependency><groupId>com.by</groupId><artifactId>dubbo_interface</artifactId><version>1.0-SNAPSHOT</version></dependency></dependencies>

HelloServiceImpl：（注意这个@Service注解是dubbo下的）

/** Copyright (c) 2020, 2024,  All rights reserved.**/
package com.by.service;import com.alibaba.dubbo.config.annotation.Service;/*** <p>Project: dubbo_parent - HelloServiceImpl</p>* <p>Powered by scl On 2024-01-17 13:57:42</p>* <p>描述：<p>** @author 孙臣龙 [[e-mail]]* @version 1.0* @since 17*/
@Service
public class HelloServiceImpl implements HelloService{@Overridepublic String hello() {return "你好啊！！！";}
}

启动类：DubboProviderApp：

/** Copyright (c) 2020, 2024,  All rights reserved.**/
package com.by;import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;/*** <p>Project: dubbo_parent - DubboProviderApp</p>* <p>Powered by scl On 2024-01-17 13:59:35</p>* <p>描述：<p>** @author 孙臣龙 [[e-mail]]* @version 1.0* @since 17*/
@SpringBootApplication
@EnableDubbo //让dubbo去扫描dubbo的注解
public class DubboProviderApp {public static void main(String[] args) {SpringApplication.run(DubboProviderApp.class,args);}
}

application.properties:

#zookeeper\u7684\u5730\u5740
dubbo.registry.address=zookeeper://127.0.0.1:2181
#\u901A\u8BAF\u534F\u8BAE\uFF1Armi\u3001http\u3001dubbo
dubbo.protocol.name=dubbo
#\u5F53\u524D\u670D\u52A1\u7684\u540D\u79F0
dubbo.application.name=dubbo-provider

3、dobbo_consumer模块

在这个模块中我们需要测试一下我们的功能。实现上个模块的接口，创建spring boot的启动类，创建配置类。

pom.xml:

<dependencies><dependency><groupId>com.by</groupId><artifactId>dubbo_interface</artifactId><version>1.0-SNAPSHOT</version></dependency></dependencies>

HelloController:(注意：@Reference也是dubbo下的)

/** Copyright (c) 2020, 2024,  All rights reserved.**/
package com.by.controller;import com.alibaba.dubbo.config.annotation.Reference;
import com.by.service.HelloService;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
/*** <p>Project: dubbo_parent - HelloController</p>* <p>Powered by scl On 2024-01-17 15:02:44</p>* <p>描述：<p>** @author 孙臣龙 [[e-mail]]* @version 1.0* @since 17*/
@Controller
public class HelloController {@Referenceprivate HelloService helloService;@RequestMapping("/hello")@ResponseBodypublic String hello(){return helloService.hello();}
}

启动类：DubboConsumerApplication：

/** Copyright (c) 2020, 2024,  All rights reserved.**/
package com.by;import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;/*** <p>Project: dubbo_parent - DubboConsumerApplication</p>* <p>Powered by scl On 2024-01-17 15:00:04</p>* <p>描述：<p>** @author 孙臣龙 [[e-mail]]* @version 1.0* @since 17*/
@SpringBootApplication
@EnableDubbo
public class DubboConsumerApplication {public static void main(String[] args) {SpringApplication.run(DubboConsumerApplication.class,args);}
}

配置文件：application.porperties

#zookeeper\u7684\u5730\u5740
dubbo.registry.address=zookeeper://127.0.0.1:2181
#\u901A\u8BAF\u534F\u8BAE\uFF1Armi\u3001http\u3001dubbo
dubbo.protocol.name=dubbo
#\u5F53\u524D\u670D\u52A1\u7684\u540D\u79F0
dubbo.application.name=dubbo-consumer
server.port=80

注意：
        1、zookeeper必须启动
        2、 @Reference 和 @Service必须到dubbo的包
        3、必须先启动provider再起consumer

        4、模块provider和consumer的端口号要区分开

结果展示：