private List<HomeworkStatOfClassDTO> genePage(List<HomeworkStatOfClassDTO> list,Integer pageIndex,Integer pageSize){
int size = 0;
if(pageIndex != null &&pageSize != null){
if(pageSize*pageIndex >= list.size()){
size = list.size();
}else{
size = pageSize*pageIndex;
}
return list.subList((pageIndex-1)*pageSize, size);
}
return null;
}