MyBatisPlus实现增删改查

MyBatisPlus实现增删改查

实体类GkUser

package com.geekmice.springbootselfexercise.entity;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
import lombok.ToString;
import org.nustaq.serialization.annotations.Serialize;

/**
 * (GkUser)实体类
 *
 * @author pingmingbo
 * @since 2024-06-21 14:05:12
 */
@TableName(value = "gk_user")
@Data
@ToString
@Serialize
public class GkUser{
    /**
    * 主键ID
    */
    @TableId(type = IdType.AUTO)
    private Long id;
    /**
    * 姓名
    */
    @TableField(value = "name")
    private String name;
    /**
    * 年龄
    */
    @TableField(value = "age")
    private Integer age;
    /**
    * 邮箱
    */
    @TableField(value = "email")
    private String email;

}

数据层GkUserDao

package com.geekmice.springbootselfexercise.dao;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.geekmice.springbootselfexercise.entity.GkUser;

/**
 * (GkUser)表数据库访问层
 *
 * @author pingmingbo
 * @since 2024-06-21 14:05:12
 */
public interface GkUserDao extends BaseMapper<GkUser> {
}

映射文件

<?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.geekmice.springbootselfexercise.dao.GkUserDao">

    <resultMap type="com.geekmice.springbootselfexercise.entity.GkUser" id="GkUserMap">
        <result property="id" column="id" jdbcType="INTEGER"/>
        <result property="name" column="name" jdbcType="VARCHAR"/>
        <result property="age" column="age" jdbcType="INTEGER"/>
        <result property="email" column="email" jdbcType="VARCHAR"/>
    </resultMap>

</mapper>

业务层GkUserService

package com.geekmice.springbootselfexercise.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.geekmice.springbootselfexercise.entity.GkUser;

/**
 * (GkUser)表服务接口
 *
 * @author pingmingbo
 * @since 2024-06-21 14:05:12
 */
public interface GkUserService extends IService<GkUser> {

}

package com.geekmice.springbootselfexercise.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.geekmice.springbootselfexercise.dao.GkUserDao;
import com.geekmice.springbootselfexercise.entity.GkUser;
import com.geekmice.springbootselfexercise.service.GkUserService;
import org.springframework.stereotype.Service;

/**
 * (GkUser)表服务实现类
 *
 * @author pingmingbo
 * @since 2024-06-21 14:05:12
 */
@Service("gkUserService")
public class GkUserServiceImpl extends ServiceImpl<GkUserDao, GkUser> implements GkUserService {
}

基本操作

package com.geekmice.springbootselfexercise.first;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.conditions.update.UpdateWrapper;
import com.geekmice.springbootselfexercise.SpringBootSelfExerciseApplication;
import com.geekmice.springbootselfexercise.dao.GkUserDao;
import com.geekmice.springbootselfexercise.entity.GkUser;
import com.geekmice.springbootselfexercise.service.GkUserService;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.collections4.CollectionUtils;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

/**
 * @BelongsProject: spring-boot-self-exercise
 * @BelongsPackage: com.geekmice.springbootselfexercise.first
 * @Author: pingmingbo
 * @CreateTime: 2024-07-09  10:12
 * @Description: mybatisplus实现增删改查
 * @Version: 1.0
 */
@SpringBootTest(classes = SpringBootSelfExerciseApplication.class)
@RunWith(SpringRunner.class)
@Slf4j
public class FirstTest {

    @Resource
    GkUserDao gkUserDao;

    @Resource
    GkUserService gkUserService;


    @Test
    public void t1() {
        // 初始数据
        // id  name age email
        // 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
        // 1、查询
        GkUser gkUser = gkUserDao.selectById(1);
        log.info("1.1、根据主键id查询 gkUser : [{}]", gkUser);

        List<GkUser> gkUsers = gkUserDao.selectList(null);
        log.info("1.2、查询所有 gkUsers : [{}]", CollectionUtils.size(gkUsers));

        // todo 分页查询 通过分页插件PaginationInnerInterceptor实现

        // 批量查询
        List<Integer> list = new ArrayList(16);
        list.add(1);
        list.add(2);
        List<GkUser> batchUsers = gkUserDao.selectBatchIds(list);
        log.info("1.3、批量主键查询 batchUsers : [{}]", CollectionUtils.size(batchUsers));
        // 根据条件批量查询
        QueryWrapper<GkUser> queryWrapper = new QueryWrapper<>();
        queryWrapper.le("id", 2);
        List<GkUser> gkUsers1 = gkUserDao.selectList(queryWrapper);
        log.info("1.4、根据条件批量查询 gkUsers1 : [{}]", CollectionUtils.size(gkUsers1));

        // 2、增加
        GkUser insertGkUser = gkUserDao.selectById(6);
        if (Objects.isNull(insertGkUser)) {
            GkUser domain = new GkUser();
            domain.setAge(10);
            domain.setEmail("test6@baomidou.com");
            domain.setName("Rose");
            gkUserDao.insert(domain);
        }
        GkUser afterInsertGkUser = gkUserDao.selectById(6);
        log.info("2.1 添加数据 afterInsertGkUser : [{}]", afterInsertGkUser);

        // 3、修改
        GkUser updateGkUser = gkUserDao.selectById(6);
        GkUser domain = new GkUser();
        if (Objects.nonNull(updateGkUser)) {
            domain.setId(6L);
            domain.setAge(6);
            domain.setEmail("test66@baomidou.com");
            domain.setName("rose");
            gkUserDao.updateById(domain);
            log.info("3.1 更新一条数据 domain ");
        }
        System.out.println("aaa");
        UpdateWrapper<GkUser> singleUpdateWrapper = new UpdateWrapper<>();
        singleUpdateWrapper.lambda().in(GkUser::getId,list);
        singleUpdateWrapper.set("name","abc");
        gkUserService.update(singleUpdateWrapper);
        log.info("3.2 定制化修改");
        // 4、删除
        // 定制化条件删除
        QueryWrapper<GkUser> deleteWrapper = new QueryWrapper<>();
        deleteWrapper.lambda().le(GkUser::getId,1);
        gkUserService.remove(deleteWrapper);
        log.info("4.1 根据条件删除");
        gkUserService.removeById(2);
        log.info("4.2 根据主键删除");


    }
}

分页查询

配置分页插件

package com.geekmice.springbootselfexercise.config;

import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @BelongsProject: spring-boot-self-exercise
 * @BelongsPackage: com.geekmice.springbootselfexercise.config
 * @Author: pingmingbo
 * @CreateTime: 2023-08-09  09:29
 * @Description: mybatis配置信息
 * @Version: 1.0
 */
@Configuration
@MapperScan(value = "com.geekmice.springbootselfexercise.dao")
public class MybatisPlusConfig {

    /**
     * 分页插件配置
     */
    @Bean(name = "mybatisPlusInterceptor")
    public MybatisPlusInterceptor mybatisPlusInterceptor (){
        MybatisPlusInterceptor interceeptor = new MybatisPlusInterceptor();
        interceeptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
        return interceeptor;
    }


}

如何使用

    Page<GkUser> gkUserPage = new Page<>(1,3);
    Page<GkUser> records = gkUserDao.selectPage(gkUserPage, null);
    log.info("records : [{}]" , records);

> Preparing: SELECT id,name,age,email FROM gk_user LIMIT ?
> Parameters: 3(Long)
< Columns: id, name, age, email
< Row: 3, Tom, 28, test3@baomidou.com
<== Row: 4, Sandy, 21, test4@baomidou.com
<== Row: 5, Billie, 24, test5@baomidou.com
<== Total: 3
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@67376bae]
2024-07-10 01:37:14.271 INFO 9164 — [ main] c.g.s.first.FirstTest : records : [com.baomidou.mybatisplus.extension.plugins.pagination.Page@135a8808]
2024-07-10 01:37:14.790 INFO 9164 — [ionShutdownHook] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown initiated…
2024-07-10 01:37:14.873 INFO 9164 — [ionShutdownHook] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown completed.

Process finished with exit code 0