springboot 以多模块形式集成Dubbo部署RPC服务

　　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。

　　https://www.cnblogs.com/personblog/p/14537931.html

　　https://www.cnblogs.com/personblog/p/13391810.html

　　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);
}

　　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：

参考:https://www.cnblogs.com/zjfjava/p/9696086.html

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原文地址：https://www.cnblogs.com/personblog/p/14553099.html

springboot 以多模块形式集成Dubbo部署RPC服务

创建公共API

服务提供者，目录结构和相关代码如下

服务消费者