MyBatis-Plus使用ActiveRecord(AR)实现CRUD

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
 
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
 
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
            <version>5.1.9</version>
        </dependency>
 
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.0.5</version>
        </dependency>

#配置数据库的相关连接信息
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/springdb?useUnicode=true&characterEncoding=UTF-8&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=GMT%2B8
spring.datasource.username=root
spring.datasource.password=12345678
 
#配置对应的日志信息
mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

package com.szh.mybatisplus.entity;
 
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.extension.activerecord.Model;
 
/**
 * 使用AR，要求实体类必须继承MP框架中的Model类
 * Model类中提供了数据库相关的CRUD操作
 */
public class Dept extends Model<Dept> {
 
    @TableId(value = "id",type = IdType.AUTO)
    private Integer id;
    private String name;
    private String mobile;
    private Integer manager;
 
    //getter and setter
    //toString
}

package com.szh.mybatisplus.mapper;
 
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.szh.mybatisplus.entity.Dept;
 
/**
 *
 */
public interface DeptMapper extends BaseMapper<Dept> {
}

package com.szh.mybatisplus;
 
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
 
@SpringBootApplication
@MapperScan(value = "com.szh.mybatisplus.mapper")
public class Application {
 
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
 
}

    @Test
    void testDeptInsert() {
        Dept dept=new Dept();
        dept.setName("销售部");
        dept.setMobile("12345678900");
        dept.setManager(1);
 
        //调用实体类对象自己的方法，完成对象自身到数据库的添加操作
        boolean flag=dept.insert();
        System.out.println("insert的结果：" + flag);
    }

    @Test
    void testDeptUpdate() {
        Dept dept=new Dept();
        dept.setId(1);
        dept.setName("研发部");
        dept.setMobile("99999999999");
        dept.setManager(2);
 
        //调用实体类对象自己的方法，完成对象自身到数据库的更新操作
        boolean flag=dept.updateById();
        System.out.println("update的结果：" + flag);
    }

    @Test
    void testDeptDelete() {
        Dept dept=new Dept();
        boolean result = dept.deleteById(2);
        System.out.println("delete的结果：" + result);
    }

    @Test
    void testDeptDelete2() {
        Dept dept=new Dept();
        dept.setId(2);
        boolean result = dept.deleteById();
        System.out.println("delete的结果：" + result);
    }

    @Test
    void testSelect() {
        Dept dept=new Dept();
        dept.setId(3);
        Dept dept1 = dept.selectById();
        System.out.println("select的结果：" + dept1);
    }

    @Test
    void testSelect2() {
        Dept dept=new Dept();
        Dept dept1 = dept.selectById(3);
        System.out.println("select的结果：" + dept1);
    }

    @Test
    void testSelect3() {
        Dept dept=new Dept();
        List<Dept> deptList=dept.selectAll();
        deptList.forEach( dept1 -> {
            System.out.println(dept1);
        });
    }