List＜Object＞转List＜User＞：

List< object>转List< User>：

List objList = dao.select…(); //Query data, but what is returned is List<Object> object

Object obj = (Object)objList; //First convert objList to Object type
　　　//Then convert object to any type you want
　　　　List<User> userList = (List<User>) Object;