springboot+mybatis 的org.mybatis.spring.MyBatisSystemException 解决方法

"nested exception is org.apache.ibatis.exceptions.PersistenceException: \r\n### Error querying database.  Cause: java.lang.UnsupportedOperationException\r\n### The error may exist in com/hiteamtech/uws/dao/AppsDao.java (best guess)\r\n### The error may involve com.hiteamtech.uws.dao.AppsDao.findAppInfoByUserId\r\n### The error occurred while handling results\r\n### SQL: SELECT id,app_name,create_time,app_Introduction,user_id from app_info where status = 1 and user_id =? order by id limit ?,?\r\n### Cause: java.lang.UnsupportedOperationException"

以下是我DAO层的代码

和CONTROLLER层代码

@Select("SELECT id,app_name,create_time,app_Introduction,user_id from app_info where status = 1 and user_id =#{userId} order by id limit #{page},#{pageCount}")List findAppInfoByUserId(@Param("userId")  int userId, @Param("page") int page1, @Param("pageCount") int pageCount);

@GetMapping(value = "/apps/{userId}/{page}/{pageCount}")public ResponseEntity<Map> findAppsByUserId(@PathVariable("userId") int userId, @PathVariable("page") int page, @PathVariable("pageCount") int pageCount,Map<String,Object> map){    log.debug("根据用户ID获取我的产品:"+ userId + "page:" + page+"pageCount:"+ pageCount);    map.put("appCount",iappService.findAppsCount(userId));    map.put("appInfo",iappService.findAppsByUserId(userId,page,pageCount));    return new  ResponseEntity<>(map,HttpStatus.OK);}

因为controller里返回的JSON数据是Map 所以不能用List 返回DAO

可以对DAO做以下修改

@Select("SELECT id,app_name,create_time,app_Introduction,user_id from app_info where status = 1 and user_id =#{userId} order by id limit #{page},#{pageCount}")List<Map<String,Object>> findAppInfoByUserId(@Param("userId")  int userId, @Param("page") int page1, @Param("pageCount") int pageCount);