SpringBoot 2.3 集成 Mybatis Plus 3.4

- 日理万妓 2022-12-03 02:24 116阅读 0赞

### 文章目录 ###

*   *   *  1 摘要
         *  2 核心依赖
         *  3 配置信息
         *   *  3.1 application.yml 配置文件
             *  3.2 分页配置
         *  4 演示数据库表
         *  5 核心代码
         *   *  5.1 实体类
             *  5.2 DAO 层
             *  5.3 请求参数类
             *  5.4 Service 层
             *  5.5 Controller 层
             *  5.6 SpringBoot 启动类
             *  5.7 Mybatis mapper 文件
             *  5.8 Swagger 接口文档
         *  6 推荐学习方法
         *   *  6.1 学习方法
             *  6.2 实践操作步骤
         *  7 推荐参考资料
         *  8 Github 源码

### 1 摘要 ###

众所周知，Mybatis 是一个优秀的数据持久层框架，有着广泛的应用，其半自动化的特性既是优点也是缺点，优点是性能高，缺点是数据库语句依然需要开发者自行编写，对于一些基础的CRUD操作，将消耗开发者的大量时间和精力。为了减少开发者重复编写基本增删改查(CRUD)操作，国内的技术团队开发并开源了 Mybatis Plus 框架，从此，程序员将更加专注于业务开发，对于简单的增删改查将不需要再手写SQL。Mybatis Plus 是基于 Mybatis 开发，对其做了增强，其根本核心依旧是 Mybatis，Mybatis 的特性也全部支持。本文将介绍基于 SpringBoot 2.3 集成 Mybatis Plus 3.4。

Mybatis Plus 官方文档: [https://baomidou.com/guide][https_baomidou.com_guide]

### 2 核心依赖 ###

./demo-mybatis-plus/pom.xml

<dependency>
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-boot-starter</artifactId>
                <version>${mybatis-plus.version}</version>
            </dependency>

其中 `${mybatis-plus.version}` 的版本号为 `3.4.0`

完整依赖参考 `pom.xml` 文件

**注意事项** : 引入 Mybatis Plus 之后就不需要再引入 `Mybatis` 的依赖，Mybatis Plus 中已经集成 Mybaits，重复依赖可能导致版本冲突的问题

### 3 配置信息 ###

#### 3.1 application.yml 配置文件 ####

./demo-mybatis-plus/src/main/resources/application.yml

## config
    
    ## server
    server:
      port: 8450
    
    ## spring config
    spring:
      datasource:
        url: "jdbc:mysql://127.0.0.1:3306/demo?useUnicode=true&characterEncoding=utf8\
          &useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=GMT%2b8\
          &useSSL=true&allowMultiQueries=true&autoReconnect=true&nullCatalogMeansCurrent=true\
          &nullCatalogMeansCurrent=true"
        username: root
        password: "root"
        hikari:
          driver-class-name: com.mysql.cj.jdbc.Driver
    
    ## mybatis-plus
    mybatis-plus:
      mapper-locations: classpath*:mybatis/*.xml
      type-aliases-package: com.ljq.dmeo.springboot.mybatisplus.model.entity
    
    ## mybatis log
    logging:
      level:
        com.ljq.demo.springboot.mybatisplus.dao: debug

**注意事项** : 在引入 `mybatis-plus-boot-starter` 依赖之后，需要使用 Mybatis Plus 对应的配置来取代旧有的 Mybatis 配置，两者的区别仅在于开头的配置(要以 `mybatis-plus` 开头),如果使用旧有的 Mybatis 配置，将不会生效，从而引起项目运行异常，如无法扫描到对应的 mapper 文件。

#### 3.2 分页配置 ####

Mybatis Plus 自带分页查询工具，但是需要手动配置

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/common/config/MybatisPlusConfig.java

package com.ljq.demo.springboot.mybatisplus.common.config;
    
    import com.baomidou.mybatisplus.annotation.DbType;
    import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
    import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    
    /** * @Description: MybatisPlus 配置信息 * @Author: junqiang.lu * @Date: 2020/9/1 */
    @Configuration
    public class MybatisPlusConfig { 
    
        /** * 新的分页插件,一缓和二缓遵循 mybatis 的规则 */
        @Bean
        public MybatisPlusInterceptor mybatisPlusInterceptor() { 
            MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
            interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.H2));
            return interceptor;
        }
    
    }

**注意事项:** 从 Mybatis Plus 3.4 开始，将使用新的分页配置，原来的分页配置类 `PaginationInterceptor` 已经被弃用

更多配置参考 Mybatis Plus 官方文档: [https://baomidou.com/guide/interceptor.html][https_baomidou.com_guide_interceptor.html]

### 4 演示数据库表 ###

./doc/sql/demo-database-create.sql

/*==============================================================*/
    /* DBMS name: MySQL 5.0 */
    /* Created on: 2018/9/29 16:10:13 */
    /*==============================================================*/
    
    
    drop database if exists `demo`;
    create database `demo` default character set utf8mb4 collate utf8mb4_general_ci;
    use `demo`;
    
    drop table if exists user;
    
    /*==============================================================*/
    /* Table: user */
    /*==============================================================*/
    create table user
    (
       id                   bigint unsigned not null auto_increment comment 'id 主键',
       user_name            varchar(30) comment '用户名',
       user_passcode        varchar(100) comment '登陆密码',
       user_email           varchar(50) comment '邮箱',
       user_insert_time     varchar(30) comment '用户注册时间',
       user_update_time     varchar(30) comment '用户更新时间',
       user_status          tinyint default 1 comment '用户账号状态,1正常(默认),2禁止登陆',
       user_version         int unsigned default 1 comment '版本控制字段(默认1)',
       user_del             tinyint default 0 comment '逻辑删除字段,0正常(默认),1删除',
       primary key (id)
    )
    ENGINE = INNODB DEFAULT
    CHARSET = UTF8MB4;
    
    alter table user comment '用户表';

初始化测试数据

./doc/sql/demo-database-test.sql

## test-demo 
    
    -- 添加测试用户 
    INSERT INTO `user`(`user_name`, `user_passcode`, `user_email`, `user_insert_time`, `user_update_time`)
      VALUES('tom', MD5('demo12345'), 'tom@example.com', NOW(), NOW()),
            ('bob', MD5('demo12345'), 'bob@example.com', NOW(), NOW()),
            ('jack', MD5('demo12345'), 'jack@example.com', NOW(), NOW()),
            ('lily', MD5('demo12345'), 'lily@example.com', NOW(), NOW()),
            ('liming', MD5('demo12345'), 'liming@example.com', NOW(), NOW());

### 5 核心代码 ###

#### 5.1 实体类 ####

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/entity/UserEntity.java

package com.ljq.demo.springboot.mybatisplus.model.entity;
    
    import com.baomidou.mybatisplus.annotation.*;
    import io.swagger.annotations.ApiModel;
    import io.swagger.annotations.ApiModelProperty;
    import lombok.Data;
    
    import java.io.Serializable;
    
    /** * 用户表实体类 * * @author junqiang.lu * @date 2020-09-01 13:24:08 */
    @Data
    @TableName(value = "user", resultMap = "userMap")
    @ApiModel(value = "用户表", description = "用户表")
    public class UserEntity implements Serializable { 
    
    	private static final long serialVersionUID = 1L;
    
         /** * id 主键 **/
        @TableId(value = "id", type = IdType.AUTO)
        @ApiModelProperty(value = "id 主键", name = "id")
        private Long id;
        /** * 用户名 **/
        @TableField(value = "user_name")
        @ApiModelProperty(value = "用户名", name = "userName")
        private String userName;
        /** * 登陆密码 **/
        @TableField(value = "user_passcode")
        @ApiModelProperty(value = "登陆密码", name = "userPasscode")
        private String userPasscode;
        /** * 邮箱 **/
        @TableField(value = "user_email")
        @ApiModelProperty(value = "邮箱", name = "userEmail")
        private String userEmail;
        /** * 用户注册时间 **/
        @TableField(value = "user_insert_time")
        @ApiModelProperty(value = "用户注册时间", name = "userInsertTime")
        private String userInsertTime;
        /** * 用户更新时间 **/
        @TableField(value = "user_update_time")
        @ApiModelProperty(value = "用户更新时间", name = "userUpdateTime")
        private String userUpdateTime;
        /** * 用户账号状态,1正常(默认),2禁止登陆 **/
        @TableField(value = "user_status")
        @ApiModelProperty(value = "用户账号状态,1正常(默认),2禁止登陆", name = "userStatus")
        private Integer userStatus;
        /** * 版本控制字段(默认1) **/
        @TableField(value = "user_version")
        @ApiModelProperty(value = "版本控制字段(默认1)", name = "userVersion")
        private Integer userVersion;
        /** * 逻辑删除字段,0正常(默认),1删除 **/
        @TableLogic(value = "0", delval = "1")
        @TableField(value = "user_del")
        @ApiModelProperty(value = "逻辑删除字段,0正常(默认),1删除", name = "userDel")
        private Integer userDel;
    
    
    }

这里使用到的Mybatis Plus 注解有:

`@TableName`: 用于指定实体类对应的数据库表

`@TableId` : 用在主键对应的属性上，可以指定主键对应的数据库字段名，同时可以指定主键的生成策略(默认使用雪花算法生成一个 `Long` 类型数字)

`@TableField` : 用在非主键对应的属性上，可以指定属性对应的数据库字段名，同时也可以设置字段是否为空等属性

`@TableLogic` : 用在标记逻辑删除的字段属性上，使用该注解后，Myabtis Plus 所有针对该表的删除都将执行逻辑删除(即更新操作)，而不使用该注解，Mybatis Plus 执行的删除操作为物理删除

更多的注解参考 Mybatis Plus 官方文档: [https://baomidou.com/guide/annotation.html][https_baomidou.com_guide_annotation.html]

#### 5.2 DAO 层 ####

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/dao/UserDao.java

package com.ljq.demo.springboot.mybatisplus.dao;
    
    import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import com.ljq.demo.springboot.mybatisplus.model.entity.UserEntity;
    import org.apache.ibatis.annotations.Mapper;
    import org.springframework.stereotype.Component;
    
    /** * 用户表 * * @author junqiang.lu * @date 2020-08-31 14:09:53 */
    @Mapper
    @Component("userDao")
    public interface UserDao extends BaseMapper<UserEntity> { 
    	
    }

开发者手写的 DAO 接口需要继承 Mybatis Plus 提供的 `com.baomidou.mybatisplus.core.mapper.BaseMapper` 接口，同时指定泛型

#### 5.3 请求参数类 ####

增删改查接口对应的请求参数封装类

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/param/UserSaveParam.java

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/param/UserInfoParam.java

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/param/UserListParam.java

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/param/UserUpdateParam.java

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/model/param/UserDeleteParam.java

完整代码参考项目 Github 源码: [https://github.com/Flying9001/springBootDemo][https_github.com_Flying9001_springBootDemo]

#### 5.4 Service 层 ####

Service 接口

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/service/UserService.java

package com.ljq.demo.springboot.mybatisplus.service;
    
    import com.ljq.demo.springboot.mybatisplus.common.api.ApiResult;
    import com.ljq.demo.springboot.mybatisplus.model.param.*;
    
    /** * 用户表业务层接口 * * @author junqiang.lu * @date 2020-08-31 14:09:53 */
    public interface UserService { 
    
    	/** * 保存(单条) * * @param userSaveParam * @return * @throws Exception */
    	ApiResult save(UserSaveParam userSaveParam) throws Exception;
    
    	/** * 查询详情(单条) * * @param userInfoParam * @return * @throws Exception */
    	ApiResult info(UserInfoParam userInfoParam) throws Exception;
    
    	/** * 查询列表 * * @param userListParam * @return * @throws Exception */
    	ApiResult list(UserListParam userListParam) throws Exception;
    
    	/** * 更新(单条) * * @param userUpdateParam * @return * @throws Exception */
    	ApiResult update(UserUpdateParam userUpdateParam) throws Exception;
    
    	/** * 删除(单条) * * @param userDeleteParam * @return * @throws Exception */
    	ApiResult delete(UserDeleteParam userDeleteParam) throws Exception;
    
    }

Service 实现类

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/service/impl/UserServiceImpl.java

package com.ljq.demo.springboot.mybatisplus.service.impl;
    
    import cn.hutool.core.bean.BeanUtil;
    import cn.hutool.core.bean.copier.CopyOptions;
    import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
    import com.baomidou.mybatisplus.core.metadata.IPage;
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import com.ljq.demo.springboot.mybatisplus.common.api.ApiResult;
    import com.ljq.demo.springboot.mybatisplus.dao.UserDao;
    import com.ljq.demo.springboot.mybatisplus.model.entity.UserEntity;
    import com.ljq.demo.springboot.mybatisplus.model.param.*;
    import com.ljq.demo.springboot.mybatisplus.service.UserService;
    import lombok.extern.slf4j.Slf4j;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    import org.springframework.transaction.annotation.Propagation;
    import org.springframework.transaction.annotation.Transactional;
    
    import java.util.Objects;
    
    /** * 用户表业务层具体实现类 * * @author junqiang.lu * @date 2020-08-31 14:09:53 */
    @Service("userService")
    @Transactional(rollbackFor = { Exception.class})
    @Slf4j
    public class UserServiceImpl implements UserService { 
    
    	@Autowired
    	private UserDao userDao;
    
    	/** * 保存(单条) * * @param userSaveParam * @return * @throws Exception */
    	@Override
    	@Transactional(propagation = Propagation.REQUIRED, rollbackFor = { Exception.class})
    	public ApiResult save(UserSaveParam userSaveParam) throws Exception { 
    		// 请求参数获取
    		UserEntity userParam = new UserEntity();
    		BeanUtil.copyProperties(userSaveParam,userParam,CopyOptions.create()
    				.setIgnoreNullValue(true).setIgnoreError(true));
    		// 保存
    		String nowTime = String.valueOf(System.currentTimeMillis());
    		userParam.setUserInsertTime(nowTime);
    		userParam.setUserUpdateTime(nowTime);
    		userDao.insert(userParam);
    
    		return ApiResult.success(userParam.getId());
    	}
    
    	/** * 查询详情(单条) * * @param userInfoParam * @return * @throws Exception */
    	@Override
    	public ApiResult info(UserInfoParam userInfoParam) throws Exception { 
    		UserEntity userDB = userDao.selectById(userInfoParam.getId());
    		return ApiResult.success(userDB);
    	}
    
    	/** * 查询列表 * * @param userListParam * @return * @throws Exception */
    	@Override
    	public ApiResult list(UserListParam userListParam) throws Exception { 
    		LambdaQueryWrapper<UserEntity> userWrapper = new LambdaQueryWrapper<>();
    		userWrapper.like(Objects.nonNull(userListParam.getUserName()), UserEntity::getUserName,
    				userListParam.getUserName());
    		IPage<UserEntity> page = new Page<>(userListParam.getCurrentPage(),userListParam.getPageSize());
    		userWrapper.orderBy(true, userListParam.isAscFlag(), UserEntity::getId);
    		page = userDao.selectPage(page, userWrapper);
    
    		return ApiResult.success(page);
    	}
    
    	/** * 更新(单条) * * @param userUpdateParam * @return * @throws Exception */
    	@Override
    	@Transactional(propagation = Propagation.REQUIRED, rollbackFor = { Exception.class})
    	public ApiResult update(UserUpdateParam userUpdateParam) throws Exception { 
    		LambdaQueryWrapper<UserEntity> userWrapper = new LambdaQueryWrapper<>();
    		userWrapper.eq(true, UserEntity::getId, userUpdateParam.getId());
    		int countUser = userDao.selectCount(userWrapper);
    		if (countUser < 1) { 
    			return ApiResult.failure("用户不存在");
    		}
    		// 请求参数获取
    		UserEntity userParam = new UserEntity();
    		BeanUtil.copyProperties(userUpdateParam, userParam, CopyOptions.create().ignoreNullValue().ignoreError());
    		userParam.setUserUpdateTime(String.valueOf(System.currentTimeMillis()));
    		userDao.updateById(userParam);
    
    		return ApiResult.success();
    	}
    
    	/** * 删除(单条) * * @param userDeleteParam * @return * @throws Exception */
    	@Override
    	@Transactional(propagation = Propagation.REQUIRED, rollbackFor = { Exception.class})
    	public ApiResult delete(UserDeleteParam userDeleteParam) throws Exception { 
    		int countUser = userDao.deleteById(userDeleteParam.getId());
    		if (countUser < 1) { 
    			return ApiResult.failure("用户不存在");
    		}
    		return ApiResult.success();
    	}	
    }

基础的增删改查在这里都有对应的示例，包括根据条件分页查询

#### 5.5 Controller 层 ####

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/controller/UserController.java

package com.ljq.demo.springboot.mybatisplus.controller;
    
    import com.ljq.demo.springboot.mybatisplus.common.api.ApiResult;
    import com.ljq.demo.springboot.mybatisplus.model.param.*;
    import com.ljq.demo.springboot.mybatisplus.service.UserService;
    import io.swagger.annotations.Api;
    import io.swagger.annotations.ApiOperation;
    import lombok.extern.slf4j.Slf4j;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.http.HttpHeaders;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.bind.annotation.*;
    
    /** * 用户表 * * @author junqiang.lu * @date 2020-08-31 16:39:56 */
    @Slf4j
    @RestController
    @RequestMapping(value = "/api/mybatis/plus/user")
    @Api(value = "用户表控制层", tags = "用户表控制层")
    public class UserController { 
    
    	@Autowired
    	private UserService userService;
    
        /** * 保存(单条) * * @param userSaveParam * @return */
        @PostMapping(value = "/add", produces = { MediaType.APPLICATION_JSON_VALUE})
        @ApiOperation(value = "用户表保存(单条)",  notes = "用户表保存(单条)")
        public ResponseEntity<?> save(@RequestBody UserSaveParam userSaveParam) throws Exception{ 
            ApiResult apiResult = userService.save(userSaveParam);
    
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_JSON);
            return new ResponseEntity<>(apiResult, headers, HttpStatus.OK);
        }
    
        /** * 查询详情(单条) * * @param userInfoParam * @return */
        @GetMapping(value = "/info", produces = { MediaType.APPLICATION_JSON_VALUE})
        @ApiOperation(value = "用户表查询详情(单条)",  notes = "用户表查询详情(单条)")
        public ResponseEntity<?> info(UserInfoParam userInfoParam) throws Exception { 
            ApiResult apiResult = userService.info(userInfoParam);
    
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_JSON);
            return new ResponseEntity<>(apiResult, headers, HttpStatus.OK);
        }
    
        /** * 查询列表 * * @param userListParam * @return */
        @GetMapping(value = "/list", produces = { MediaType.APPLICATION_JSON_VALUE})
        @ApiOperation(value = "用户表查询列表",  notes = "用户表查询列表")
        public ResponseEntity<?> list(UserListParam userListParam) throws Exception { 
            ApiResult apiResult = userService.list(userListParam);
    
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_JSON);
            return new ResponseEntity<>(apiResult, headers, HttpStatus.OK);
        }
    
        /** * 修改(单条) * * @param userUpdateParam * @return */
        @PutMapping(value = "/update", produces = { MediaType.APPLICATION_JSON_VALUE})
        @ApiOperation(value = "用户表修改(单条)",  notes = "用户表修改(单条)")
        public ResponseEntity<?> update(@RequestBody UserUpdateParam userUpdateParam) throws Exception { 
            ApiResult apiResult = userService.update(userUpdateParam);
    
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_JSON);
            return new ResponseEntity<>(apiResult, headers, HttpStatus.OK);
        }
    
        /** * 删除(单条) * * @param userDeleteParam * @return */
        @DeleteMapping(value = "/delete", produces = { MediaType.APPLICATION_JSON_VALUE})
        @ApiOperation(value = "用户表删除(单条)",  notes = "用户表删除(单条)")
        public ResponseEntity<?> delete(@RequestBody UserDeleteParam userDeleteParam) throws Exception { 
            ApiResult apiResult = userService.delete(userDeleteParam);
    
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_JSON);
            return new ResponseEntity<>(apiResult, headers, HttpStatus.OK);
        }
    
    }

#### 5.6 SpringBoot 启动类 ####

./demo-mybatis-plus/src/main/java/com/ljq/demo/springboot/mybatisplus/DemoMybatisPlusApplication.java

package com.ljq.demo.springboot.mybatisplus;
    
    import org.mybatis.spring.annotation.MapperScan;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import springfox.documentation.swagger2.annotations.EnableSwagger2;
    
    /** * @author junqiang.lu */
    @EnableSwagger2
    @SpringBootApplication(scanBasePackages = { "com.ljq.demo.springboot.mybatisplus.*"})
    @MapperScan(basePackages = { "com.ljq.demo.springboot.mybatisplus.dao"})
    public class DemoMybatisPlusApplication { 
    
        public static void main(String[] args) { 
            SpringApplication.run(DemoMybatisPlusApplication.class, args);
        }
    
    }

**注意事项:** 需要使用 `@MapperScan` 指定扫描 mapper 所在的包，即 DAO 层

#### 5.7 Mybatis mapper 文件 ####

使用 Mybatis Plus 之后，依旧可以使用 mapper 文件，尽管一些基本的增删改查不需要再手写 SQL了，但是作者还是建议保留 mapper 文件，对于一些复杂的查询，手写 SQL 可能更加简洁

./demo-mybatis-plus/src/main/resources/mybatis/UserDao.xml

<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
    
    <mapper namespace="com.ljq.demo.springboot.mybatisplus.dao.UserDao">
    
    	
        <resultMap type="com.ljq.demo.springboot.mybatisplus.model.entity.UserEntity" id="userMap">
            <result property="id" column="id"/>
            <result property="userName" column="user_name"/>
            <result property="userPasscode" column="user_passcode"/>
            <result property="userEmail" column="user_email"/>
            <result property="userInsertTime" column="user_insert_time"/>
            <result property="userUpdateTime" column="user_update_time"/>
            <result property="userStatus" column="user_status"/>
            <result property="userVersion" column="user_version"/>
            <result property="userDel" column="user_del"/>
        </resultMap>
    
       
    	<sql id="user_base_field">
            `id`,
            `user_name`,
            `user_passcode`,
            `user_email`,
            `user_insert_time`,
            `user_update_time`,
            `user_status`,
            `user_version`,
            `user_del`
    	</sql>
    
    </mapper>

Mybatis Plus 同样可以指定 mapper 文件中定义的 `resultMap` ，具体使用到的注解为实体类上 `@TableName`

#### 5.8 Swagger 接口文档 ####

启动项目，打开浏览器，输入地址:

http://127.0.0.1:8450/swagger-ui.html

即可进行接口测试

至此基于 SpringBoot 2.x 集成 Mybatis Plus 3.4 已经完成

### 6 推荐学习方法 ###

#### 6.1 学习方法 ####

**有问题,先搜索,然后查阅官方文档,找到对应的说明**

#### 6.2 实践操作步骤 ####

*  1 按照官方文档启动项目
 *  2 实现基本的增删改查
 *  3 实现一些高级功能,如指定 resultMap,逻辑删除等等

### 7 推荐参考资料 ###

[MybatisPlus 官方文档][MybatisPlus]

[MybatisPlus–3.5 指定查询列][MybatisPlus_3.5]

[MyBatis-Plus 用起来真的很舒服][MyBatis-Plus]

[mybatis-plus配置找不到Mapper接口路径的坑][mybatis-plus_Mapper]

[MyBatis-Plus 分页查询以及自定义sql分页][MyBatis-Plus _sql]

### 8 Github 源码 ###

**Gtihub 源码地址** : [https://github.com/Flying9001/springBootDemo][https_github.com_Flying9001_springBootDemo]

个人公众号:**404Code**,分享半个互联网人的技术与思考，感兴趣的可以关注.  
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[https_baomidou.com_guide]: https://baomidou.com/guide
[https_baomidou.com_guide_interceptor.html]: https://baomidou.com/guide/interceptor.html
[https_baomidou.com_guide_annotation.html]: https://baomidou.com/guide/annotation.html
[https_github.com_Flying9001_springBootDemo]: https://github.com/Flying9001/springBootDemo
[MybatisPlus]: https://baomidou.com
[MybatisPlus_3.5]: https://blog.csdn.net/cheng_cuo_tuo/article/details/104523103
[MyBatis-Plus]: https://www.cnblogs.com/l-y-h/p/12859477.html
[mybatis-plus_Mapper]: https://blog.csdn.net/u013234928/article/details/94060733
[MyBatis-Plus _sql]: https://blog.csdn.net/weixin_38111957/article/details/91554108
[404Code]: /images/20221123/2d96a5bd2ad14978ac0d2d89fcf82daf.png