list对象转成以字段名为key，该字段所有值为[]

1.从数据库中取出数据，需要将数据封装成根据字段名能够取出所有字段值。 mapper文件

<select id="getUser" parameterType="java.lang.String" resultType="java.util.Map"> select fdId,docSubject,fd_sqr as fdSqr from table_1 where doccode=#{docCode} </select>

dao层

@Mapper public interface UserDao{ /** *查询所有同一年龄的人 * @param age 年龄 * @return 数据Map */ List<Map<String, Object>> getUser(String age); }

service层

import cn.hutool.core.map.MapUtil; import lombok.extern.slf4j.Slf4j; import org.apache.commons.collections.CollectionUtils; import org.apache.commons.lang3.StringUtils; import org.sun.common.api.vo.Result; import org.sun.modules.user.mapper.UserDao; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.ArrayList; import java.util.List; import java.util.Map; @Slf4j @Service public class UserServiceImpl { @Autowired private UserDao userDao; public Result getSupplier(String age) { try { List<Map<String, Object>> list = new ArrayList<>(); list = userDao.getUser(age); if (CollectionUtils.isEmpty(list)) { return Result.error(); } Map<String, List<Object>> maps = MapUtil.toListMap(list); return Result.ok(); } catch (Exception e) { log.error("失败，失败原因：" + e.getMessage()); return Result.error("失败，失败原因：" + e.getMessage()); } }

划重点： https://hutool.cn/docs/index.html#/core/Map/Map%E5%B7%A5%E5%85%B7-MapUtil?id=%e6%96%b9%e6%b3%95