5.ResultMap

在实际项目开发, 我们的数据表字段和我们的domain对象可能不太一样,所以我们需要借助 ResultMap 标签来封装对象返回数据信息

 

UserMapper.xml 配置

<?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="com.gzcgxt.oa.mapper.UserMapper">
    
    <resultMap id="UserMap" type="User">
        <id column="u_id" property="id"/>
        <result column="u_name" property="name"/>
    </resultMap>
    
    <select id="find" resultMap="UserMap">
        SELECT * FROM `user` WHERE u_id=#{u_id} 
    </select>
    
     <select id="listAll" resultMap="UserMap">
        SELECT * FROM `user` ORDER BY u_id desc
    </select>
    
</mapper>

代码如下