1. 入门案例
问题导入
MyBatisPlus环境搭建的步骤?
1.1 SpringBoot整合MyBatisPlus入门程序
①:创建新模块,选择Spring初始化,并配置模块相关基础信息
②:选择当前模块需要使用的技术集(仅保留JDBC)
③:手动添加MyBatisPlus起步依赖
<dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.4.1</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.1.16</version> </dependency
注意事项1:由于mp并未被收录到idea的系统内置配置,无法直接选择加入
注意事项2:如果使用Druid数据源,需要导入对应坐标
④:制作实体类与表结构
(类名与表名对应,属性名与字段名对应)
create database if not exists mybatisplus_db character set utf8; use mybatisplus_db; CREATE TABLE user ( id bigint(20) primary key auto_increment, name varchar(32) not null, password varchar(32) not null, age int(3) not null , tel varchar(32) not null ); insert into user values(null,'tom','123456',12,'12345678910'); insert into user values(null,'jack','123456',8,'12345678910'); insert into user values(null,'jerry','123456',15,'12345678910'); insert into user values(null,'tom','123456',9,'12345678910'); insert into user values(null,'snake','123456',28,'12345678910'); insert into user values(null,'张益达','123456',22,'12345678910'); insert into user values(null,'张大炮','123456',16,'12345678910');
public class User { private Long id; private String name; private String password; private Integer age; private String tel; //自行添加getter、setter、toString()等方法 }
⑤:设置Jdbc参数(application.yml)
spring: datasource: type: com.alibaba.druid.pool.DruidDataSource driver-class-name: com.mysql.cj.jdbc.Driver url: jdbc:mysql://localhost:3306/mybatisplus_db?serverTimezone=UTC username: root password: root
⑥:定义数据接口,继承BaseMapper
package com.itheima.dao; import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.itheima.domain.User; import org.apache.ibatis.annotations.Mapper; @Mapper public interface UserDao extends BaseMapper<User> { }
⑦:测试类中注入dao接口,测试功能
package com.itheima; import com.itheima.dao.UserDao; import com.itheima.domain.User; import org.junit.jupiter.api.Test; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.context.SpringBootTest; import java.util.List; @SpringBootTest public class Mybatisplus01QuickstartApplicationTests { @Autowired private UserDao userDao; @Test void testGetAll() { List<User> userList = userDao.selectList(null); System.out.println(userList); } }
2. MyBatisPlus概述
问题导入
通过入门案例制作,MyBatisPlus的优点有哪些?
2.1 MyBatis介绍
MyBatisPlus(简称MP)是基于MyBatis框架基础上开发的增强型工具,旨在简化开发、提高效率
官网:https://mybatis.plus/https://mp.baomidou.com/
无侵入:只做增强不做改变,不会对现有工程产生影响
强大的 CRUD 操作:内置通用 Mapper,少量配置即可实现单表CRUD 操作
支持 Lambda:编写查询条件无需担心字段写错
支持主键自动生成
内置分页插件
……