//删除roomSchedule :cry:
List<TRoomSchedule> roomScheduleList = IAS.getTRoomScheduleByAppointId(open.getAppointId(),"A");
if(roomScheduleList != null && roomScheduleList.size() > 0){
TRoomSchedule roomSchedule = roomScheduleList.get(0);
ICS.delete(roomSchedule);
}
今天编写程序,遇到list index out of bounds的异常,原因出在roomScheduleList.get(0);这句话,百度了一下,说的很贴切,和大家分享:
引用
举个形象的例子,我有一个空着的水杯(list),而你没有,那你是null,我的size为0。你想装水需要去买个水杯(new ArrayList();),我就可以直接装水(list.add(水))。你要是没有杯子直接倒水,水就流出去啦(空指针异常)。所以用做判断的时候经常连用 list!=null && list.size()!=0 。
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