mybatis的增删改查运用方式

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "https://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <!--数据库信息-->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/><!--改：数据库的固定连接，老版本不用cj-->
                <property name="url" value="jdbc:mysql://localhost:3306/mishop?useSSL=false&amp;serverTimezone=UTC"/><!--mishop改：数据库的要连接的库-->
                <property name="username" value="root"/><!--改：数据库的账号-->
                <property name="password" value="root"/><!--改：数据库的密码-->
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--加载映射文件-->
        <mapper resource="com/project/Mapper/AdminMapper.xml"/><!--改：把映射文件的源根路径复制到这里-->
    </mappers>
</configuration>

package com.project.pojo;
 
 
public class Admin {
    private Integer adminId;
    private String adminName;
    private String adminPwd;
    private Integer adminDisable;
 
    public Integer getAdminId() {
        return adminId;
    }
 
    public void setAdminId(Integer adminId) {
        this.adminId = adminId;
    }
 
    public String getAdminName() {
        return adminName;
    }
 
    public void setAdminName(String adminName) {
        this.adminName = adminName;
    }
 
    public String getAdminPwd() {
        return adminPwd;
    }
 
    public void setAdminPwd(String adminPwd) {
        this.adminPwd = adminPwd;
    }
 
    public Integer getAdminDisable() {
        return adminDisable;
    }
 
    public void setAdminDisable(Integer adminDisable) {
        this.adminDisable = adminDisable;
    }
 
    public Admin(Integer adminId, String adminName, String adminPwd, Integer adminDisable) {
        this.adminId = adminId;
        this.adminName = adminName;
        this.adminPwd = adminPwd;
        this.adminDisable = adminDisable;
    }
 
    public Admin() {
    }
 
    @Override
    public String toString() {
        return "Admin{" +
                "adminId=" + adminId +
                ", adminName='" + adminName + '\'' +
                ", adminPwd='" + adminPwd + '\'' +
                ", adminDisable=" + adminDisable +
                '}';
    }
}

package com.project.Mapper;
 
import com.project.pojo.Admin;
 
import java.util.List;
public interface AdminMapper {
    //增
    // void (封装类 封装类小写)
    //括号要用封装类是因为表里面那行数据都要进行增加
    void add (Admin admin);
 
    //改
    // void 自定义名称 (封装类 封装类小写);
    //括号要用封装类是因为表里面那行数据都要进行增加
    void updateId(Admin admin);
 
    //查全部
    // list <pojo封装类> 自定义全部查询();
    //因为是查询全部，所以括号里面不用加任何参数
    List<Admin> selectAll();
 
    //查单个
    //list <pojo封装类> 自定义全部查询(自定义参数根据id查询);
    List<Admin> selectId(int id);
 
 
    //删
    // void 自定义名称 (自定义参数为要根据id进行删除);
    void deleteId(int id);
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
 
<!--sql映射查询方法-->
 
<!--namespace=对应接口的全部路径-->
<mapper namespace="com.project.Mapper.AdminMapper">
        <!--新增的SQL语句    -->
        <!--第一行：insert新增标签 id="接口定义的名字"  parameterType="封装类的全限名"     -->
        <!--第二行：SQL语句-自增id用null，其他的用#{封装类的属性名} ,....   -->
    <insert id="add" parameterType="com.project.pojo.Admin">
        insert into admin values (null,#{adminName},#{adminPwd},#{adminDisable})
    </insert>
 
        <!--删除的SQL语句    -->
        <!-- 第一行:delete删除标签 id="接口定义的名字"  parameterType="封装类的全限名"   -->
        <!--第二行：SQL语句-根据id（封装的属性）进行删除    -->
    <delete id="deleteId" parameterType="com.project.pojo.Admin">
        delete from admin where adminId=#{adminId}
    </delete>
 
        <!--修改的SQL语句    -->
        <!--第一行：update修改标签  id="接口定义的名字"  parameterType="封装类的全限名"   -->
        <!-- 第二行：SQL语句-因为要修改的是那行的全部数据，所以封装的属性都要一一对应写出来    -->
    <update id="updateId" parameterType="com.project.pojo.Admin">
        update admin set adminName=#{adminName},adminPwd=#{adminPwd},adminDisable=#{adminDisable} where adminId=#{adminId}
    </update>
 
    <!--查询全部的SQL语句    -->
    <!-- 第一行：select查询标签  resultType="封装类的权限定名"  -->
    <select id="selectAll" resultType="com.project.pojo.Admin">
        select * from admin
    </select>
    <!-- 查询单个的SQL语句  如上 -->
    <select id="selectId" resultType="com.project.pojo.Admin">
        select * from admin where AdminId=#{adminId}
    </select>
 
</mapper>

package com.project.pojo;
 
import com.project.Mapper.AdminMapper;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
 
import java.io.IOException;
import java.io.InputStream;
 
 
public class AdminImpl {
    public static void main(String[] args) throws IOException {
 
        //1.加载mybatis连接文件（核心配置文件）
        String resource = "mybatis-config.xml";//这是连接数据库的
        InputStream inputStream = Resources.getResourceAsStream(resource);//固定写法
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);//固定写法
 
        //2.获取sqlSessionFactory对象--固定的写法
        SqlSession sqlSession = sqlSessionFactory.openSession();
 
        //3.执行sql语句
        AdminMapper adminMapper = sqlSession.getMapper(AdminMapper.class);
 
 
        //以下这些用哪个执行哪个
 
/*         // 添加的方法
        Admin admin = new Admin();
        admin.setAdminName("wangwu");
        admin.setAdminPwd("8888");
        admin.setAdminDisable(54);
        //Mapper接口里面的添加方法
        adminMapper.add(admin);
        */
 
 
/*        Mapper接口里面的删除方法
        adminMapper.deleteId(14);
        */
 
 
/*      修改的方法
        Admin admin = new Admin();
        admin.setAdminId(7);
        admin.setAdminName("王五");
        admin.setAdminPwd("123456");
        admin.setAdminDisable(5555);
        //Mapper接口里面的修改方法
        adminMapper.updateId(admin);
        */
 
 
/*      查询单个的方法，Mapper接口里面的查询方法
        List<Admin> selectId = adminMapper.selectId(5);
        System.out.println(selectId);
        */
 
/*        //查询全部的方法
        List<Admin> selectAll = adminMapper.selectAll();
        System.out.println(selectAll);*/
        
        //提交
        sqlSession.commit();
 
        //6.释放资源
        sqlSession.close();
    }
 
}