springboot学习-springboot引入MyBatis-Plus

1 功能实现

2、根据springboot版本复制依赖配置到pom.xml，如当前用的springboot3&maven，则复制依赖配置

3、添加mysql依赖

XML 复制代码

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.33</version>
</dependency>

4、添加项目配置

XML 复制代码

spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/app_db?allowPublicKeyRetrieval=true&userSSL=false&characterEncoding=utf8
    username: root
    password: 123456
mybatis-plus:
  mapper-locations: classpath:mapper/*.xml

5、添加mapperscan注解

6、引入Lombok依赖

XML 复制代码

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

7、创建实体类

java 复制代码

package com.jay.mes.entity;

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

@Data
@TableName("`user_info`")
public class UserInfo {
    private Long id;
    private String name;
    private Integer age;
    private String email;
}

8、创建mapper类

java 复制代码

package com.jay.mes.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.jay.mes.entity.UserInfo;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface UserInfoMapper extends BaseMapper<UserInfo>{

}

8、创建service接口和service的实现类

UserInfoService.java

java 复制代码

package com.jay.mes.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.jay.mes.entity.UserInfo;

public interface UserInfoService extends IService<UserInfo> {
}

UserInfoServiceImpl.java

java 复制代码

package com.jay.mes.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.jay.mes.entity.UserInfo;
import com.jay.mes.mapper.UserInfoMapper;
import com.jay.mes.service.UserInfoService;
import org.springframework.stereotype.Service;

@Service
public class UserInfoServiceImpl extends ServiceImpl<UserInfoMapper, UserInfo> implements UserInfoService {
}

2 测试

打开测试类
使用@Resource注解实例化Mapper对象
添加测试代码
点击测试按钮

java 复制代码

package com.jay.mes;

import com.jay.mes.entity.UserInfo;
import com.jay.mes.mapper.UserInfoMapper;
import jakarta.annotation.Resource;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest
class MesApplicationTests {

    @Resource
    private UserInfoMapper userInfoMapper;
    @Test
    void contextLoads() {
        System.out.println("----- test query -----");
        List<UserInfo> userInfos = userInfoMapper.selectList(null);
        userInfos.forEach(System.out::println);
    }

}