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福永网站推广,灰色词快速排名接单,深圳网站建设定制开发超凡科技,建设社区网站有什么借鉴之处前言我们在开发中经常需要操作数据库，传统的mybatis需要编写mapper和xml文件，工作量比较大，可以集成mybatisplus减少代码量，提高开发效率 MybatisPlus介绍简介 | MyBatis-Plus MyBatis-Plus 是一个 MyBatis 的增强工具&…

前言

我们在开发中经常需要操作数据库，传统的mybatis需要编写mapper和xml文件，工作量比较大，可以集成mybatisplus减少代码量，提高开发效率

MybatisPlus介绍

简介 | MyBatis-Plus

MyBatis-Plus 是一个 MyBatis 的增强工具，在 MyBatis 的基础上只做增强不做改变，为简化开发、提高效率而生。

添加表及数据

DROP TABLE IF EXISTS `user`;CREATE TABLE `user`
(id BIGINT NOT NULL COMMENT '主键ID',name VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名',age INT NULL DEFAULT NULL COMMENT '年龄',email VARCHAR(50) NULL DEFAULT NULL COMMENT '邮箱',PRIMARY KEY (id)
);

DELETE FROM `user`;INSERT INTO `user` (id, name, age, email) VALUES
(1, 'Jone', 18, 'test1@baomidou.com'),
(2, 'Jack', 20, 'test2@baomidou.com'),
(3, 'Tom', 28, 'test3@baomidou.com'),
(4, 'Sandy', 21, 'test4@baomidou.com'),
(5, 'Billie', 24, 'test5@baomidou.com');

创建工程添加依赖

创建一个空的 Spring Boot 工程，引入 MyBatis-Plus Starter 依赖

添加了mybatisPlus的依赖就不需要添加mybatis的了，以免冲突

Spring Boot2

<dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.5.11</version>
</dependency>

Spring Boot3

<dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-spring-boot3-starter</artifactId><version>3.5.11</version>
</dependency>

        <!-- 数据库驱动（以 MySQL 为例） --><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><scope>runtime</scope></dependency>

配置

spring:application:name: joinDemodatasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/sbdemousername: rootpassword: 123456hikari:maximum-pool-size: 10connection-timeout: 30000mybatis-plus:configuration:log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

在 Spring Boot 启动类中添加 @MapperScan 注解，扫描 Mapper 文件夹：

@SpringBootApplication
@MapperScan("com.sky.joindemo.mapper")
public class JoinDemoApplication {public static void main(String[] args) {SpringApplication.run(JoinDemoApplication.class, args);}}

类

@Getter
@Setter
@ToString
@Accessors(chain = true)
public class User implements Serializable {private static final long serialVersionUID = 1L;/*** 主键ID*/@TableId(type = IdType.AUTO)private Long id;/*** 姓名*/private String name;/*** 年龄*/private Integer age;/*** 邮箱*/private String email;
}

/*** <p>*  Mapper 接口* </p>** @author sky* @since 2025-03-25*/
public interface UserMapper extends BaseMapper<User> {}

单元测试


import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.sky.joindemo.entity.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;import java.util.List;@SpringBootTest
class UserMapperTest {@Autowiredprivate UserMapper userMapper;@Testpublic void testSelect() {System.out.println(("----- selectAll method test ------"));List<User> userList = userMapper.selectList(null);Assert.isTrue(5 == userList.size(), "");userList.forEach(System.out::println);}@Testpublic void testSelectByWrapper() {//实体类上添加这个注解，可以链式访问@Accessors(chain = true)User user = new User().setName("Jack").setAge(18);QueryWrapper<User> queryWrapper = new QueryWrapper<>();queryWrapper.like(!StringUtils.isEmpty(user.getName()), "name", user.getName()).eq(user.getAge() != null, "age", user.getAge());List<User> userList = userMapper.selectList(queryWrapper);userList.forEach(System.out::println);}@Testpublic void testSelectByLambdaQueryWrapper() {User user = new User().setName("Jack").setAge(18);LambdaQueryWrapper<User> lambdaQueryWrapper = new LambdaQueryWrapper<>();lambdaQueryWrapper.like(!StringUtils.isEmpty(user.getName()),User::getName, "Jack").eq(user.getAge() != null,User::getAge, 18);List<User> userList = userMapper.selectList(lambdaQueryWrapper);userList.forEach(System.out::println);}
}

代码生成器

使用代码生成器的话要引入

		<!-- 模板引擎 --><dependency><groupId>org.apache.velocity</groupId><artifactId>velocity-engine-core</artifactId><version>2.3</version></dependency>


import com.baomidou.mybatisplus.generator.FastAutoGenerator;
import com.baomidou.mybatisplus.generator.engine.VelocityTemplateEngine;import java.nio.file.Paths;
import java.util.Scanner;public class CodeGenerator {public static void main(String[] args) {Scanner scanner = new Scanner(System.in);System.out.println("请输入要生成代码的表名，多个表名用逗号分隔：");String tableNamesInput = scanner.nextLine();String[] tableNames = tableNamesInput.split(",");FastAutoGenerator.create("jdbc:mysql://localhost:3306/sbdemo", "root", "123456").globalConfig(builder -> builder.author("sky")// 开启 swagger 模式.outputDir(Paths.get(System.getProperty("user.dir")) + "/src/main/java").commentDate("yyyy-MM-dd")).packageConfig(builder -> builder.parent("com.sky.joindemo").entity("entity").mapper("mapper").service("service").serviceImpl("service.impl").xml("mapper.xml")).strategyConfig(builder -> builder.addInclude(tableNames).entityBuilder().enableLombok()).templateEngine(new VelocityTemplateEngine()).execute();}
}