Spring整合MyBatisPlus

MyBatisPlus官网

1. 引入Maven依赖

<dependency>
  <groupId>com.baomidou</groupId>
  <artifactId>mybatis-plus-boot-starter</artifactId>
  <version>3.4.0</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
</dependency>

2. 编写Entity和Mapper类并设置扫描范围

也可以用EasyCode等代码生成工具生成，请参考《EasyCode自动生成代码》

生成的Entity类：

package com.spring.accumulator.entity;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;

import java.io.Serializable;

import lombok.NoArgsConstructor;
import lombok.Data;

/**
 * (Person)表实体类
 *
 * @author wangrubin
 * @since 2022-07-15 18:22:45
 */
@Data
@NoArgsConstructor
@TableName("person")
public class PersonPO implements Serializable {

    private String name;

    private Integer male;

    private Integer age;

    @TableId(value = "id", type = IdType.AUTO)
    private Long id;
}

生成Mapper类

package com.spring.accumulator.dao;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.spring.accumulator.entity.PersonPO;
import org.apache.ibatis.annotations.Mapper;

/**
 * (Person)表数据库访问层
 *
 * @author wangrubin
 * @since 2022-07-15 18:22:45
 */
@Mapper
public interface PersonMapper extends BaseMapper<PersonPO> {
}

配置@MapperScan，使Mapper类可被MyBatisPlus识别

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.spring.accumulator.dao")
public class AccumulatorApplication {

    public static void main(String[] args) {
        SpringApplication.run(AccumulatorApplication.class, args);
    }

}

3. 配置文件中增加MySQL数据库的连接配置

spring.datasource.url=jdbc:mysql://localhost:3306/wangrubin_db?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&tinyInt1isBit=false&&useSSL=false&&rewriteBatchedStatements=true
spring.datasource.driverClassName=com.mysql.cj.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=mysql

4. 测试MyBatisPlus的功能

package com.spring.accumulator;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.spring.accumulator.dao.PersonMapper;
import com.spring.accumulator.entity.PersonPO;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
@ContextConfiguration(classes = AccumulatorApplication.class)
public class MyBatisPlusTest {
    @Resource
    private PersonMapper personMapper;

    @Test
    public void testQueryWrapper() {
        QueryWrapper<PersonPO> queryWrapper = new QueryWrapper<>();
        queryWrapper.lambda().eq(PersonPO::getId, 1L);
        PersonPO personPo = personMapper.selectOne(queryWrapper);
        System.out.println(personPo);
    }

5. 总结

本文整理了Spring Boot整合MyBatisPlus的必要步骤和最基本操作，要想深入探索MyBatisPlus的更多功能，请查阅MyBatisPlus官网文档。