mybatis的简单使用步骤

由于第一次写服务端，犯了很多错误，自己写的JDBC连接在运行时一直断开导致数据没办法实时保存，查询后决定使用mybatis.因为以前是Android开发，所以选用了gradle构建项目。
步骤一、首先在build.gradle中添加要用到的依赖

    implementation 'mysql:mysql-connector-java:8.0.33'
    implementation 'org.mybatis:mybatis:3.5.4'
    implementation group: 'com.baomidou', name: 'mybatis-plus-boot-starter', version: '3.5.1'

步骤二、配置mybatis
在recourses目录中添加mybatis-config.xml

image.png

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
      <configuration>
          <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC">
                <property name="closeConnection" value="false"/>
            </transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3307/face"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
        </dataSource>
        </environment>
        </environments>
        <mappers>
        <mapper resource="mybatis/myMapper.xml"/>
        </mappers>
        </configuration>

其中closeConnection设置为false，数据库连接不断开。

<mapper resource="mybatis/myMapper.xml"/>

myMapper.xml文件用于定于数据库操作的SQL语句，下面是myMapper.xml的内容。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
      <mapper namespace="org.hkwy.mapper.RecordMapper">
    <insert id="addKaoQin" parameterType="org.hkwy.bean.KaoQin">
        INSERT INTO KaoQin (name, job_num,time,pass,kqj_num) VALUES (#{name}, #{job_num},#{time},#{pass},#{kqj_num})
    </insert>
    <select id="queryKaoQinList" resultType="org.hkwy.bean.KaoQin">
        SELECT *FROM kaoqin
    </select>
    <update id="updateKaoQin" parameterType="org.hkwy.bean.KaoQin">
        UPDATE kaoqin set job_num = #{job_num} WHERE name = #{name}
    </update>
</mapper>

步骤三、创建数据模型

public class KaoQin {
    private String job_num;//员工编号
    private String name;//员工姓名
    private String time;//打开时间

    public String getJob_num() {
        return job_num;
    }

    public void setJob_num(String job_num) {
        this.job_num = job_num;
    }

    public String getKqj_num() {
        return kqj_num;
    }

    public void setKqj_num(String kqj_num) {
        this.kqj_num = kqj_num;
    }

    private String pass;// 1-通过 0-不通过
    private String kqj_num;//考勤机编号

    public String getName() {
        return name;
    }

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


    public String getTime() {
        return time;
    }

    public void setTime(String time) {
        this.time = time;
    }

    public String getPass() {
        return pass;
    }

    public void setPass(String pass) {
        this.pass = pass;
    }
}

步骤四、定义数据库操作接口(与myMapper.xml中的sql相对应)

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.hkwy.bean.KaoQin;

import java.util.List;

public interface RecordMapper extends BaseMapper<KaoQin>{

    /**
     * 插入一条打卡记录
     * @param recogniseResult
     * @return
     */
    Integer addKaoQin(KaoQin recogniseResult);
    List<KaoQin> queryKaoQinList();
    void updateKaoQin(KaoQin recogniseResult);
}

步骤五、执行

try {
                InputStream resourceAsStream = Resources.getResourceAsStream("mybatis-config.xml");
                SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);

                SqlSession sqlSession = sqlSessionFactory.openSession();
                RecordMapper recordMapper = sqlSession.getMapper(RecordMapper.class);
                KaoQin record=new KaoQin();
                record.setJob_num("293");
                record.setName("lilii");
                record.setPass("1");
                record.setTime("2024-02-24 10:10:59");
                record.setKqj_num("8169023060000990");
                int value=recordMapper.addKaoQin(record);
                if (sqlSession != null) {
                    sqlSession.commit();
                    sqlSession.close();
                }
            }catch (IOException e){
                e.printStackTrace();
            }
        }