springboot整合mybatis入门程序

1.准备工作(创建springboot工程、数据库表user、实体类User)

       

 创建数据表：

create table user(
                     id int unsigned primary key auto_increment comment 'ID',
                     name varchar(100) comment '姓名',
                     age tinyint unsigned comment '年龄',
                     gender tinyint unsigned comment '性别, 1:男, 2:女',
                     phone varchar(11) comment '手机号'
) comment '用户表';

insert into user(id, name, age, gender, phone) VALUES (null,'白眉鹰王',55,'1','18800000000');
insert into user(id, name, age, gender, phone) VALUES (null,'金毛狮王',45,'1','18800000001');
insert into user(id, name, age, gender, phone) VALUES (null,'青翼蝠王',38,'1','18800000002');
insert into user(id, name, age, gender, phone) VALUES (null,'紫衫龙王',42,'2','18800000003');
insert into user(id, name, age, gender, phone) VALUES (null,'光明左使',37,'1','18800000004');
insert into user(id, name, age, gender, phone) VALUES (null,'光明右使',48,'1','18800000005');

 创建实体类：

/*
 * Copyright (c) 2020, 2023,  All rights reserved.
 *
 */
package com.example.springbootmybatis.pojo;

/**
 * 
Project: spring-boot-mybatis - User
 * 
Powered by scl On 2023-10-07 10:12:33
 * 
描述：

 *
 * @author 孙臣龙 [[email protected]]
 * @version 1.0
 * @since 17
 */
public class User {
    private Integer id;
    private String name;
    private short age;
    private short gender;
    private String phone;

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", gender=" + gender +
                ", phone='" + phone + '\'' +
                '}';
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public short getAge() {
        return age;
    }

    public void setAge(short age) {
        this.age = age;
    }

    public short getGender() {
        return gender;
    }

    public void setGender(short gender) {
        this.gender = gender;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public User(Integer id, String name, short age, short gender, String phone) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.gender = gender;
        this.phone = phone;
    }

    public User() {
    }
}

2.引入Mybatis的相关依赖，配置Mybatis(数据库连接信息)

 

 配置文件：

#驱动类名称
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
#数据库连接的url
spring.datasource.url=jdbc:mysql://localhost:3306/mybatis
#连接数据库的用户名
spring.datasource.username=root
#连接数据库的密码
spring.datasource.password=

3.编写SQL语句(注解/XML)

编写mapper接口：

package com.example.springbootmybatis.mapper;

import com.example.springbootmybatis.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

/**
 * 
Project: spring-boot-mybatis - UserMapper
 * 
Powered by scl On 2023-10-07 10:17:12
 * 
描述：

 *
 * @author 孙臣龙 [[email protected]]
 * @version 1.0
 * @since 17
 */
@Mapper //在运行时会自动生成实现类对像，并交给ioc容器管理
public interface UserMapper {
    @Select("select * from user")
    public List list();
}

编写测试类：

package com.example.springbootmybatis;

import com.example.springbootmybatis.mapper.UserMapper;
import com.example.springbootmybatis.pojo.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest
class SpringBootMybatisApplicationTests {

    @Autowired
    private UserMapper userMapper;
    @Test
    public void testListUser(){
        List userList=userMapper.list();
        userList.stream().forEach(user -> {
            System.out.println(user);
        });
    }

}