搭建MyBatis-Plus框架并进行数据库添加
MyBatis-Plus（简称 MP）是一个 MyBatis 的增强工具，在 MyBatis 的基础上只做增强不做改变，为简化开发、提高效率而生。
Jdk：jdk1.8.0_261
Idea：IntelliJ IDEA
Maven：apache-maven-3.3.6
MySQL：mysql-5.5.61
创建数据库
CREATE DATABASE tzy03;
USE tzy03;
CREATE TABLE user(
id INT(11) PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(50),
pass VARCHAR(50),
);
INSERT INTO user(name,passs) VALUES('Tom','1215');
SELECT * FROM user;
新建完成以后，打开pom.xml后添加以下依赖：
<dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>3.4.0</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.49</version> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <version>1.18.12</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-test</artifactId> </dependency>
扫描mapper层
package com.tzy.demo;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@MapperScan("com.tzy.demo.mapper")
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
成功界面
package com.tzy.demo.pojo;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
public class user {
@TableId(value = "id")
public int id;
@TableField(value = "name")
public String name;
@TableField(value = "pass")
public String pass;
@Override
public String toString() {
return "user{" +
"id=" + id +
", name='" + name + '\'' +
", pass='" + pass + '\'' +
'}';
}
public user(){}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPass() {
return pass;
}
public void setPass(String pass) {
this.pass = pass;
}
}
package com.tzy.demo.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.tzy.demo.pojo.user;
import org.springframework.stereotype.Repository;
@Repository
public interface Userdao extends BaseMapper<user> {
}
在test文件里自动生成DemoApplicationTests类里往数据库中添加数据进行测试。
package com.tzy.demo;
import com.tzy.demo.mapper.Userdao;
import com.tzy.demo.pojo.user;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
@SpringBootTest
class DemoApplicationTests {
@Autowired
private Userdao userdao;
@Test
void insert(){
user user1=new user();
user1.setName("田哲沅");
user1.setPass("1218");
int result=userdao.insert(user1);
System.out.println("result:"+result);
System.out.println(user1);//id会自动回填到user对象中
}
}
成功界面
需求信息：将id为1的员工的姓名更改为"tzy"
@Test
void testUpdateById() {
user user2=userdao.selectById(1);
user2.setName("tzy");
int result = userdao.updateById(user2);
System.out.println(result);
}
}
查询id为1的员工信息
@Test
void selectById() {
user user2=userdao.selectById(1);
System.out.println(user2);
}
}
删除id为1的员工信息
@Test
void testDeleteById() {
int result = userdao.deleteById(1);
System.out.println(result);
}
