1 理论

消费者A和消费者B分别部署在两台机器上

一般将User类定义为独立模块，A模块和B模块都通过maven依赖于该模块即可

• dubbo 内部已经将序列化和反序列化的过程内部封装了

• 只需要在定义pojo类时实现Serializable接口即可

• 一般会定义一个公共的pojo模块，让生产者和消费者都依赖该模块。

2 实践

package com.yppah.pojo;

import java.io.Serializable;

/**
 * @Author: haifei
 * @Date: 2022/10/14 22:24
 */
public class User implements Serializable {

    private int id;
    private String username;
    private String password;

    // 快捷键：alt + insertwedfd
    public User(int id, String username, String password) {
        this.id = id;
        this.username = username;
        this.password = password;
    }

    public User() {
    }

    // 快捷键：alt + insert
    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.yppah</groupId>
    <artifactId>dubbo-interface</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>com.yppah</groupId>
            <artifactId>dubbo-pojo</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>

</project>

package com.yppah.service;

import com.yppah.pojo.User;

/**
 * @Author: haifei
 * @Date: 2022/10/9 0:06
 */
public interface UserService {

    public String sayHello();

    /**
     * 查询用户
     */
    public User findUserById(int id);
}

package com.yppah.service.impl;

import com.yppah.pojo.User;
import com.yppah.service.UserService;
import org.apache.dubbo.config.annotation.Service;
//import org.springframework.stereotype.Service;

/**
 * @Author: haifei
 * @Date: 2022/10/9 0:07
 */
//@Service //定义bean：将该类的对象创建出来，放到spring的IOC容器中
@Service //将该类提供的方法(服务)对外发布，将访问地址(ip,端口,路径)注册到注册中心中(zk)
public class UserServiceImpl implements UserService {

    @Override
    public String sayHello() {
        return "hello dubbo! hihihi";
    }

    @Override
    public User findUserById(int id) {
        // 查询User对象
        User user = new User(1, "zhangsan", "123");
        return user;
    }
}

package com.yppah.controller;

//import com.yppah.service.UserService;
import com.yppah.pojo.User;
import com.yppah.service.UserService;
import org.apache.dubbo.config.annotation.Reference;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @Author: haifei
 * @Date: 2022/10/9 0:30
 */
@RestController
@RequestMapping("/user")
public class UserController {

    //@Autowired//本地注入
    /*
        1. 从注册中心zk获取useService的访问url
        2. 进行远程调用RPC
        3. 将结果封装为一个代理对象，并给变量赋值
     */
    @Reference//远程注入
    private UserService userService;

    @RequestMapping("/sayHello")
    public String sayHello(){
        return userService.sayHello();
    }

    /**
     * 根据id查询用户信息
     * @param id
     * @return
     */
    @RequestMapping("/findUser")
    public User findUser(int id){
        return userService.findUserById(id);
    }
}

• pojo模块被interface模块依赖
• 而service模块和web模块又依赖于interface模块
• 所以service模块和web模块间接依赖于pojo模块
• 启动顺序：pojo模块install，interface模块install，service模块和web模块tomcat-run
• 注意：被依赖的模块有了改动后，一定要重新install后才能生效

访问<localhost:8000/user/findUser.do?id=1>测试