Mybatis中实体类属性与数据列表间映射方法介绍

public class User implements Serializable {
  private Integer userId;
  private String userName;
  ......
}

<mapper namespace="data.UserMapper">
  <resultMap type="data.User" id="userResultMap">
    <!-- 用id属性来映射主键字段 -->
    <id property="id" column="user_id"/>
    <!-- 用result属性来映射非主键字段 -->
    <result property="userName" column="user_name"/>
  </resultMap>
</mapper>

@Select("select * from t_user where user_name = #{userName}")
@Results(
    @Result(property = "userId", column = "user_id"),
    @Result(property = "userName", column = "user_name")
)
User getUserByName(@Param("userName") String userName);

SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
Configuration configuration = new Configuration();
configuration.setMapUnderscoreToCamelCase(true);
sqlSessionFactoryBean.setConfiguration(configuration);

@Select("select user_name as userName, user_id as userId from t_user where user_name = #{userName}")
User getUserByName(@Param("userName") String userName);