一、分层领域模型规约

DO（Data Object）：与数据库表结构一一对应，通过DAO层向上传输数据源对象。
DTO（Data Transfer Object）：数据传输对象，service或manager向外传输的对象。
BO（Business Object）：业务对象。由service层输出的封装业务逻辑的对象。
AO（Application Object）：应用对象。在web层与service层之间抽象的复用对象模型，极为贴近展示层，复用度不高。
VO（View Object）：显示层对象，通常是web向模板渲染引擎层传输的对象。
Query：数据查询对象，各层接收上层的查询请求。注意超过2个参数的查询封装，禁止使用map类来传输。

目的是为了保证RPC传输数据的安全性的问题。

二、整合数据库DB层

相关测试表结构

CREATE TABLE `demo_user` (
  `user_id` int(11) NOT NULL AUTO_INCREMENT,
  `user_name` varchar(255) DEFAULT NULL,
  `user_pwd` varchar(255) DEFAULT NULL,
  `user_age` int(3) DEFAULT NULL,
  `user_addres` varchar(255) DEFAULT NULL,
  `user_integral` int(10) DEFAULT NULL,
  PRIMARY KEY (`user_id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

三、整合mybatisplus

1. Maven依赖

<dependencies>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-boot-starter</artifactId>
        <version>3.4.1</version>
    </dependency>
</dependencies>

2. application.yml 新增

spring:
  application:
    ###服务的名称
    name: demo-member
  cloud:
    nacos:
      discovery:
        ###nacos注册地址
        server-addr: 127.0.0.1:8848
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/demo-member?useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8
    username: root
    password: root

logging:
  level:
    ###打印mybatis日志
    com.demo.api.impl.mapper : debug
server:
  port: 7000

3. 实体类

com.demo.api.impl.entity

package com.demo.api.impl.entity;

import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;

/**
 * @Author: JYC
 * @Title: UserEntity
 * @Description: TODO
 * @Date: 2022/4/24 20:17
 */
@Data
@TableName("demo_user")
public class UserDo {
    @TableId
    private Integer userId;
    private String userName;
    private String userPwd;
    private Integer userAge;
    private String userAddres;
    private Integer userIntegral;
}

4. UserMapper

package com.demo.api.impl.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.demo.api.impl.entity.UserDo;

/**
 * @Author: JYC
 * @Title: UserMapper
 * @Description: TODO
 * @Date: 2022/4/24 20:20
 */
public interface UserMapper  extends BaseMapper<UserDo> {
}

5. 错误代码演示

MemberService

package com.demo.api.member;

import com.demo.api.base.BaseResponse;
import com.demo.api.member.dto.req.UserReqDto;
import com.demo.api.member.dto.resp.UserRespDto;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;

import java.util.Map;

public interface MemberService {
    @GetMapping("memberToWeiXin")
    String memberToWeiXin(Integer a);

    /**
     * 不符合规范
     * @return
     */
    @GetMapping("addMember")
    BaseResponse<String> addMember(String userName, String pwd, Integer age);

    /**
     * updateUser
     * @param map
     * @return
     */
    @PostMapping("updateUser")
    Object updateUser(@RequestBody Map<String, String> map);
}

MemberServiceImpl

package com.demo.api.impl.member;

import com.alibaba.fastjson.JSON;
import com.demo.api.base.BaseApiService;
import com.demo.api.base.BaseResponse;
import com.demo.api.impl.entity.UserDo;
import com.demo.api.impl.feign.WeChatServiceFeign;
import com.demo.api.impl.mapper.UserMapper;
import com.demo.api.member.MemberService;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

/**
 * @Author: JYC
 * @Title: MemberServiceImpl
 * @Description: TODO
 * @Date: 2022/4/24 14:37
 */
@RestController
public class MemberServiceImpl extends BaseApiService implements MemberService {
    @Autowired
    private WeChatServiceFeign weChatServiceFeign;
    @Autowired
    private UserMapper userMapper;

    @Override
    public String memberToWeiXin(Integer a) {
        // Feign调用微信服务接口
        return weChatServiceFeign.getWeChat(a);
    }

    @Override
    public BaseResponse<String> addMember(String userName, String pwd, Integer age) {
        if (StringUtils.isEmpty(userName)) {
            return setResultError("userName is null");
        }
        int j = 1 / age;
        return setResultSuccess();
    }

    @Override
    public Object updateUser(Map<String, String> map) {
        //1.接受参数
        String jsonStr = JSON.toJSONString(map);
        UserDo user = JSON.parseObject(jsonStr, UserDo.class);
        Integer userId = user.getUserId();
        //2.update
        int i = userMapper.updateById(user);
        if (i <= 0) {
            return "error";
        }
        //3.查询db数据
        UserDo userDo = userMapper.selectById(userId);
        return userDo == null ? "error" : userDo;
    }
}

测试请求接口：
127.0.0.1:7000/updateUser

请求参数：

{
    "userId": "1",
    "userName": "demo",
    "userPwd": "123",
    "userAge": "22",
    "userAddres": "杭州市",
    "userIntegral": "888"

}

响应内容：

{
    "userId": 1,
    "userName": "demo",
    "userPwd": "123",
    "userAge": 22,
    "userAddres": "杭州市",
    "userIntegral": 888
}

结果：可以注入修改userPwd、积分，返回用户的密码 等铭感信息。

6. 改造成dto转化

请求包名：com.demo.api.member.dto.req
响应包名：com.demo.api.member.dto.resp

7. 新增： reqdto

package com.demo.api.member.dto.req;

import lombok.Data;

/**
 * @Author: JYC
 * @Title: UserReqDto
 * @Description: TODO
 * @Date: 2022/4/24 22:50
 */
@Data
public class UserReqDto {
    private Integer userId;
    private String userName;
    private Integer userAge;
    private String userAddres;
}

8. 新增： respdto

package com.demo.api.member.dto.resp;

import lombok.Data;

/**
 * @Author: JYC
 * @Title: UserRespDto
 * @Description: TODO
 * @Date: 2022/4/24 22:52
 */
@Data
public class UserRespDto {
    private Integer userId;
    private String userName;
    private Integer userAge;
    private String userAddres;
    private Integer userIntegral;
}

9. dto与do转换工具类

com.demo.api.utils

package com.demo.api.utils;

import org.springframework.beans.BeanUtils;

/**
* @Author: JYC
* @Title: BeanUtils
* @Description: dto与do转换工具
* @Date: 2022/4/24 22:58
*/
public class DemoBeanUtils<Dto, Do> {
   /**
    * dto 转换为Do 工具类
    */
   public static <Do> Do dtoToDo(Object dtoEntity, Class<Do> doClass) {
       // 判断dto是否为空!
       if (dtoEntity == null) {
           return null;
       }
       // 判断DoClass 是否为空
       if (doClass == null) {
           return null;
       }
       try {
           Do newInstance = doClass.newInstance();
           BeanUtils.copyProperties(dtoEntity, newInstance);
           // Dto转换Do
           return newInstance;
       } catch (Exception e) {
           return null;
       }
   }

   /**
    * do 转换为Dto 工具类
    */
   public static <Dto> Dto doToDto(Object doEntity, Class<Dto> dtoClass) {
       // 判断dto是否为空!
       if (doEntity == null) {
           return null;
       }
       // 判断DoClass 是否为空
       if (dtoClass == null) {
           return null;
       }
       try {
           Dto newInstance = dtoClass.newInstance();
           BeanUtils.copyProperties(doEntity, newInstance);
           // Dto转换Do
           return newInstance;
       } catch (Exception e) {
           return null;
       }
   }
}

10. BaseApiService 新增 dtoTodoApi

    /**
     * dto 转换do
     *
     * @param dtoEntity
     * @param doClass
     * @param <Do>
     * @return
     */
    public static <Do> Do dtoToDo(Object dtoEntity, Class<Do> doClass) {
        return DemoBeanUtils.dtoToDo(dtoEntity, doClass);
    }

    /**
     * do转换成dto
     * @param doEntity
     * @param dtoClass
     * @param <Dto>
     * @return
     */
    public static <Dto> Dto doToDto(Object doEntity, Class<Dto> dtoClass) {
        return DemoBeanUtils.doToDto(doEntity, dtoClass);
    }

    public BaseResponse<T> setResultDb(int dbCount, T successMsg, String errorMsg) {
        return dbCount > 0 ? setResultSuccess(successMsg) :
                setResultError(errorMsg);
    }

11. 接口：

@PostMapping("updateUserDto")
BaseResponse<UserRespDto> updateUserDto(@RequestBody UserReqDto userReqDto);

12. Impl

    @Override
    public BaseResponse<UserRespDto> updateUserDto(UserReqDto userReqDto) {
        // 1.验证参数
        // 2.userReqDto
        // 3.userReqDto属性值复制 userDo
        UserDo updateUserDo = doToDto(userReqDto, UserDo.class);
        // 4.updateById
        int i = userMapper.updateById(updateUserDo);
        if (i <= 0) {
            return setResultError("修改失败！");
        }
        // 5.查询db数据
        Integer userId = updateUserDo.getUserId();
        UserDo getDbUserDo = userMapper.selectById(userId);
        if(getDbUserDo == null){
            return setResultError("查询数据为空！");
        }
        // UserDo 转化成dto
        UserRespDto userRespDto = doToDto(getDbUserDo, UserRespDto.class);
        return setResultSuccess(userRespDto);
    }

127.0.0.1:7000/updateUserDto
请求参数：

{
    "userId": "1",
    "userName": "demo",
    "userPwd": "123",
    "userAge": "22",
    "userAddres": "杭州市",
    "userIntegral": "888"

}

响应内容：

{
    "code": 200,
    "msg": "success",
    "data": {
        "userId": 1,
        "userName": "demo",
        "userAge": 22,
        "userAddres": "杭州市",
        "userIntegral": 888
    }
}