MybatisPlus入门程序

参考资料:MybatisPlus官网

 

环境搭建

创建数据库


CREATE
DATABASE `mybatisplus` ​ USE `mybatisplus` ​ CREATE TABLE `user`( id BIGINT(20) NOT NULL COMMENT '主键ID', NAME VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名', age INT(11) 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');

数据库名为 mybatisplus,表名为 user

 

创建一个springboot项目,一个web依赖即可

 

导入相关maven依赖

mysql


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

 

Lombok(不是必须品,只是可以偷点懒)


<
dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.12</version> <optional>true</optional> </dependency>

 

mybatis-plus


<dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.0.5</version> </dependency>

 

配置application.properties


# mysql spring.datasource.username=root spring.datasource.password=123456 spring.datasource.url=jdbc:mysql://localhost:3306/mybatisplus?useSSL=false
&useUnicode=true&characterEncoding=UTF-8&serverTimezone=GMT%2B8 # 东8时区,serverTimezone=GMT%2B8 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver ​ # 配置日志,方便查看SQL语句 mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

 

实体类Pojo

User


package
com.zy.pojo; ​ import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; ​ @Data @AllArgsConstructor @NoArgsConstructor public class User { ​ private Long id; private String name; private Integer age; private String email; ​ }

 

mapper接口

  实现 BaseMapper 接口

UserMapper


package
com.zy.mapper; ​ import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.zy.pojo.User; import org.springframework.stereotype.Repository; ​ @Repository //代表持久层 //在对应的mapper上面 继承 基本的接口BaseMapper public interface UserMapper extends BaseMapper<User> { //继承之后,所有的CRUD就完成了 ​ }

 

主启动类扫描mapper

 
package com.zy; ​ import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; ​ //扫描mapper文件夹 @MapperScan("com.zy.mapper") ​ @SpringBootApplication public class DemoApplication { ​ public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } ​ }

 

测试查找全部用户


@Test
public void select(){ ​ //查询全部用户 List<User> users = userMapper.selectList(null); users.forEach(System.out::println); ​ }

结果

 

 

posted @ 2020-04-05 21:07  LonZyuan  阅读(500)  评论(0编辑  收藏