spring-boot 速成(7) 集成dubbo

github上有一个开源项目spring-boot-starter-dubbo 提供了spring-boot与dubbo的集成功能，直接拿来用即可。（记得给作者点赞，以示感谢！）

下面是使用步骤，先看下工程的大致结构：

一、引入相关的依赖项

 subprojects {
     buildscript {
         ext {
             springBootVersion = '1.5.3.RELEASE'
         }
         repositories {
             mavenLocal()
             maven {
                 url "http://maven.aliyun.com/nexus/content/groups/public/"
             }
             mavenCentral()
         }
         dependencies {
             classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
         }
     }

     apply plugin: "java"
     apply plugin: "maven"
     apply plugin: 'idea'

     targetCompatibility = 1.8
     sourceCompatibility = 1.8

     repositories {
         mavenLocal()
         maven {
             url "http://maven.aliyun.com/nexus/content/groups/public/"
         }
         mavenCentral()
     }

     configurations.all {
         resolutionStrategy.cacheChangingModulesFor 1, "minutes"
     }

     dependencies {
         compile('io.dubbo.springboot:spring-boot-starter-dubbo:1.0.0')
         compile('org.springframework.boot:spring-boot-starter-web:1.5.3.RELEASE')
     }
 }

这是最外层根目录下的build.gradle，关键地方就是最后dependencies引入的2个依赖项

二、service-api中定义接口

 package com.cnblogs.yjmyzz.service.api;

 /**
  * Created by 菩提树下的杨过(http:/yjmyzz.cnblogs.com) on 2017/5/21.
  */
 public interface DemoService {
     String hello(String nickName);
 }

这一步平淡无奇，没什么好说的

三、service-provider

3.1 提供接口实现

 package com.cnblogs.yjmyzz.service.impl;

 import com.alibaba.dubbo.config.annotation.Service;
 import com.cnblogs.yjmyzz.service.api.DemoService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 /**
  * Created by 菩提树下的杨过(http:/yjmyzz.cnblogs.com) on 2017/5/21.
  */
 @Service(version = "1.0.0")
 public class DemoServiceImpl implements DemoService {

     Logger logger = LoggerFactory.getLogger(DemoServiceImpl.class);

     public String hello(String nickName) {
         logger.info(nickName + " call me!");
         return String.format("hi , %s!", nickName);
     }
 }

常规套路，不用多说

3.2 编写ServiceProvider主类

 package com.cnblogs.yjmyzz.service;

 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;

 /**
  * Created by yangjunming on 2017/5/21.
  */
 @SpringBootApplication
 public class ServiceProvider {
     public static void main(String[] args) {
         SpringApplication.run(ServiceProvider.class, args);
     }
 }

仍然是spring-boot的经典套路，跟dubbo也没任何关系

3.3 application.yml配置

 server:
   port: 8001

 spring:
   dubbo:
     scan: com.cnblogs.yjmyzz.service
     application:
       name: provider
     registry:
       address: zookeeper://127.0.0.1:2181
     protocol:
       name: dubbo
       port: 20880

这里是重点，指定了dubbo服务提供方启动所需的zk注册地址，协议类型及端口，包括扫描的包。

四、service-consumer

4.1 定义一个辅助用的Proxy

 package com.cnblogs.yjmyzz.service.proxy;

 import com.alibaba.dubbo.config.annotation.Reference;
 import com.cnblogs.yjmyzz.service.api.DemoService;
 import org.springframework.stereotype.Component;

 /**
  * Created by yangjunming on 2017/5/21.
  */
 @Component
 public class ServiceProxy {

     @Reference(version = "1.0.0")
     public DemoService demoService;
 }

就是一个标准的spring组件(不管是叫proxy还是叫container都无所谓，随个人喜好)，在该组件中持有对Service的引用实例，注意：如果指定了version，则该版本号要与service-provider中的版本号一致

4.2 调用服务

 package com.cnblogs.yjmyzz.service;

 import com.cnblogs.yjmyzz.service.proxy.ServiceProxy;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.ConfigurableApplicationContext;

 /**
  * Created by 菩提树下的杨过(http:/yjmyzz.cnblogs.com) on 2017/5/21.
  */
 @SpringBootApplication
 public class ServiceConsumer {

     public static void main(String[] args) {
         ConfigurableApplicationContext ctx = SpringApplication.run(ServiceConsumer.class, args);
         ServiceProxy proxy = ctx.getBean(ServiceProxy.class);
         System.out.println(proxy.demoService.hello("菩提树下的杨过"));//调用服务
     }
 }

一看即明，不多解释。

4.3 application.yml配置

 server:
   port: 8002

 spring:
   dubbo:
     scan: com.cnblogs.yjmyzz.service
     application:
       name: consumer
     registry:
       address: zookeeper://127.0.0.1:2181

ok，搞定！

上述示例源代码，已托管至github，有需要的朋友自行下载：https://github.com/yjmyzz/spring-boot-dubbo-demo