注:本实例是在dubbo-admin和zookeeper,已安装好的前提下操作的,关于两个的安装可以查看我前面的博客。
RPC的内容:远程过程调用,简单实现对User根据ID进行查询服务。
- 创建一个Maven空项目,作为项目的父工程,此工程的子项目基于Spring Boot 2.3.7 实现
在父模块下,需要创建的子模块
<!-- 模块说明:这里声明多个子模块 -->
<modules>
<module>dubblo-interface</module>
<module>user-service-provider</module>
<module>order-service-consumer</module>
</modules>
完整父pom结构
<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<!-- 基本信息 -->
<modelVersion>4.0.0</modelVersion>
<name>dubblo</name>
<packaging>pom</packaging>
<description>Demo project for Spring Boot</description>
<!-- 项目说明:这里作为聚合工程的父工程 -->
<groupId>com.howdy</groupId>
<artifactId>dubblo</artifactId>
<version>1.0-SNAPSHOT</version>
<!-- 模块说明:这里声明多个子模块 -->
<modules>
<module>dubblo-interface</module>
<module>user-service-provider</module>
<module>order-service-consumer</module>
</modules>
<properties>
<java.version>1.8</java.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<spring-boot.version>2.3.7.RELEASE</spring-boot.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>${spring-boot.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!-- 版本说明:这里统一管理依赖的版本号 -->
<dependency>
<groupId>com.howdy</groupId>
<artifactId>dubblo-interface</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.howdy</groupId>
<artifactId>user-service-provider</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.howdy</groupId>
<artifactId>order-service-consumer</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
<encoding>UTF-8</encoding>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.3.7.RELEASE</version>
<configuration>
<mainClass>com.howdy.dubblo.DubbloApplication</mainClass>
<classifier>exec</classifier>
</configuration>
<executions>
<execution>
<id>repackage</id>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
创建好的时目录结构如下,父级项目中的src文件及子文件用不到,可以删除掉
- 创建子模块,比如创建dubblo-interface子模块,在dubblo上右键--New--Module
其它默认,直接下一步即可
创建公共API
pom文件如下
<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>dubblo</artifactId>
<groupId>com.howdy</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<groupId>com.howdy</groupId>
<artifactId>dubblo-interface</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<!-- SLf4j 日志记录-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
<version>1.18.12</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.54</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-core</artifactId>
</dependency>
</dependencies>
</project>
相关代码如下:
package com.howdy.dubblo.bean;
import lombok.Data;
import org.springframework.stereotype.Component;
import java.util.Date;
//通过这个注解,可以不用写gettersetter方法
@Data
@Component
public class UserBean {
private int id;
private String uname;
private int uage;
private Date create_time;
}
package com.howdy.dubblo.service;
import com.howdy.dubblo.bean.UserBean;
import org.springframework.stereotype.Repository;
import java.util.List;
@Repository
public interface Order_Service {
List<UserBean> InitOrder(int userId);
}
package com.howdy.dubblo.service;
import com.howdy.dubblo.bean.UserBean;
import org.springframework.stereotype.Repository;
import java.util.List;
@Repository
public interface User_infoService {
List<UserBean> getUserList(int userId);
}
服务提供者,目录结构和相关代码如下
pom文件:
<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.howdy</groupId>
<artifactId>user-service-provider</artifactId>
<version>0.0.1-SNAPSHOT</version>
<parent>
<groupId>com.howdy</groupId>
<artifactId>dubblo</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<properties>
<spring-boot.version>2.3.7.RELEASE</spring-boot.version>
</properties>
<dependencies>
<!-- 引入公共API,以实现其接口 -->
<dependency>
<groupId>com.howdy</groupId>
<artifactId>dubblo-interface</artifactId>
</dependency>
<!-- 引入spring-boot-starter以及dubbo和curator的依赖 -->
<dependency>
<groupId>com.alibaba.boot</groupId>
<artifactId>dubbo-spring-boot-starter</artifactId>
<version>0.2.0</version>
</dependency>
<!-- Spring Boot相关依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<version>${spring-boot.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>${spring-boot.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<!--该插件主要用途:构建可执行的JAR -->
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
dubbo提供了@Service注解,可将类声明为提供方,省去了大量配置的麻烦
package com.howdy.userserviceprovider.service.impl;
import com.alibaba.dubbo.config.annotation.Service;
import com.howdy.dubblo.bean.UserBean;
import com.howdy.dubblo.service.User_infoService;
import org.springframework.stereotype.Component;
import java.util.*;
@Service //属于Dubbo的@Service注解,非Spring 作用:暴露服务
@Component
public class UserServiceImpl implements User_infoService {
@Override
public List<UserBean> getUserList(int userId) {
List<UserBean> list=new ArrayList<UserBean>();
UserBean userBean=new UserBean();
userBean.setId(1);
userBean.setUname("张三");
userBean.setUage(20);
userBean.setCreate_time(new Date());
list.add(userBean);
return list;
}
}
通过属性配置的方式设置application.properties
#当前服务/应用的名字
dubbo.application.name=user-service-provider
#注册中心的协议和地址
dubbo.registry.protocol=zookeeper
dubbo.registry.address=127.0.0.1:2181
#通信规则(通信协议和接口)
dubbo.protocol.name=dubbo
dubbo.protocol.port=20880
#连接监控中心
dubbo.monitor.protocol=registry
#开启包扫描,可替代 @EnableDubbo 注解
##dubbo.scan.base-packages=com.howdy.dubblo
springboot容器根据配置启动服务提供方,这里需要添加 @EnableDubbo 注解
package com.howdy.userserviceprovider;
import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
// 开启基于注解的dubbo功能(主要是包扫描@DubboComponentScan)
// 也可以在配置文件中使用dubbo.scan.base-package来替代 @EnableDubbo
@EnableDubbo
@SpringBootApplication
public class UserServiceProviderApplication {
public static void main(String[] args) {
SpringApplication.run(UserServiceProviderApplication.class, args);
}
}
服务方启动成功,如图:
服务消费者
消费者工程在初始化时设置为web项目,结构如下
pom文件:
<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>dubblo</artifactId>
<groupId>com.howdy</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<groupId>com.howdy</groupId>
<artifactId>order-service-consumer</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<!-- 引入公共API,以实现其接口 -->
<dependency>
<groupId>com.howdy</groupId>
<artifactId>dubblo-interface</artifactId>
</dependency>
<!-- 引入spring-boot-starter以及dubbo和curator的依赖 -->
<dependency>
<groupId>com.alibaba.boot</groupId>
<artifactId>dubbo-spring-boot-starter</artifactId>
<version>0.2.0</version>
</dependency>
<!-- Spring Boot相关依赖 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- springboot web模块 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<!--该插件主要用途:构建可执行的JAR -->
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
dubbo提供了@Reference注解,可替换@Autowired注解,用于引入远程服务
package com.howdy.orderserviceconsumer.service.impl;
import com.alibaba.dubbo.config.annotation.Reference;
import com.howdy.dubblo.bean.UserBean;
import com.howdy.dubblo.service.Order_Service;
import com.howdy.dubblo.service.User_infoService;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Service;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
@Service //属于spring注解,引入springframework.stereotype.Service 包
@Component
public class OrderServiceImpl implements Order_Service {
@Reference(version = "*", check = true)
User_infoService user_infoService;
@Override
public List<UserBean> InitOrder(int userId) {
List<UserBean> list=new ArrayList<UserBean>();
UserBean userBean=new UserBean();
userBean.setId(2);
userBean.setUname("李四");
userBean.setUage(30);
userBean.setCreate_time(new Date());
list.add(userBean);
return list;
}
}
package com.howdy.orderserviceconsumer.controller;
import com.howdy.dubblo.bean.UserBean;
import com.howdy.dubblo.service.Order_Service;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
@RestController //以json格式返回
@RequestMapping("/api")
public class OrderController {
@Autowired
Order_Service orderService;
@GetMapping("/initOrder")
public List<UserBean> initOrder(@RequestParam("uid") int userId){
return orderService.InitOrder(1);
}
}
配置文件application.properties
#避免和监控中心端口冲突,设为8081端口访问
server.port=8081
#当前服务/应用的名字
dubbo.application.name=order-service-consumer
dubbo.registry.address=zookeeper://127.0.0.1:2181
dubbo.monitor.protocol=registry
启动类同样加上@EnableDubbo注解
package com.howdy.orderserviceconsumer;
import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@EnableDubbo
@SpringBootApplication
public class OrderServiceConsumerApplication {
public static void main(String[] args) {
SpringApplication.run(OrderServiceConsumerApplication.class, args);
}
}
启动消费方,测试调用,成功如下: