參考資料：MybatisPlus官網
環境搭建
創建數據庫
CREATE DATABASE `mybatisplus` USE `mybatisplus` CREATE TABLE `user`( id BIGINT(20) NOT NULL COMMENT '主鍵ID', NAME VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名', age INT(11) NULL DEFAULT NULL COMMENT '年齡', email VARCHAR(50) NULL DEFAULT NULL COMMENT '郵箱', 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');
數據庫名為 mybatisplus，表名為 user
創建一個springboot項目，一個web依賴即可
導入相關maven依賴
mysql
<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency>
Lombok(不是必須品，只是可以偷點懶)
<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 # 東8時區，serverTimezone=GMT%2B8 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver # 配置日志,方便查看SQL語句 mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
實體類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
實現 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 //代表持久層 //在對應的mapper上面 繼承 基本的接口BaseMapper public interface UserMapper extends BaseMapper<User> { //繼承之后，所有的CRUD就完成了 }
主啟動類掃描mapper
package com.zy; import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; //掃描mapper文件夾 @MapperScan("com.zy.mapper") @SpringBootApplication public class DemoApplication { public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } }
測試查找全部用戶
@Test public void select(){ //查詢全部用戶 List<User> users = userMapper.selectList(null); users.forEach(System.out::println); }
結果
