[Rooms{roomId=null, roomType='null', roomStatus='null', checkinDate=null, checkoutDate=null, guestName='null', contactNumber='null', status='0', updateDate=null, createDate=null}, Rooms{roomId=null, roomType='null', roomStatus='null', checkinDate=null, checkoutDate=null, guestName='null', contactNumber='null', status='0', updateDate=null, createDate=null}]
原因:表中字段和实体类没有映射关系
解决方法1:
1.把实体类中的属性全部改为和数据库一致的
解决方法2:
查询的时候,给字段名取别名
String sql="select `room_id` roomId,`room_type` roomType,`room_status`, `checkin_date`,`checkout_date`,`guest_name`,contact_number,status,update_date, create_date from rooms where room_id=?";