mybatis-plus-入门使用

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引入Pom文件

        <!-- 数据库驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!-- lombok 简化set get toString -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!-- mybatis-plus -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.4.3.1</version>
        </dependency>

SQL

DROP TABLE IF EXISTS user;

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)
);
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');

userMapper

package com.no.seckill.dao;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.no.seckill.entity.User;
import org.springframework.stereotype.Repository;

@Repository
public interface UserMapper extends BaseMapper<User> {
}

实体类

package com.no.seckill.entity;

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;
}

启动类

package com.no.seckill;

import org.apache.ibatis.annotations.Mapper;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.method.annotation.ExceptionHandlerMethodResolver;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;

@SpringBootApplication
@MapperScan("com.no.seckill.dao")
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);

    }
}

测试类

package com.no.seckill;

import com.no.seckill.dao.UserMapper;
import com.no.seckill.entity.User;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest()
public class Test {
    @Autowired
    private UserMapper userMapper;
    @org.junit.Test
    public void test(){
        User user = userMapper.selectById(1);
        System.out.println(user.toString());
    }

}