java - How to split an ArrayList<E> into ArrayList<ArrayList<E>>? -

i'm pretty new java , trying create arraylist<arraylist<integer>> arraylist<integer> (splitting 28800 data points pieces of 300).

public static arraylist<arraylist<integer>> createlistofarrays(arraylist<integer> list) {      arraylist<arraylist<integer>> listofarrays = new arraylist<arraylist<integer>>();     arraylist<integer> temp = new arraylist<integer>();      (int = 0; < list.size(); i++) {         int arrayint = list.get(i);         temp.add(arrayint);          if (temp.size() % 300 == 0) {             listofarrays.add(temp);             temp.clear();         }     }      return listofarrays;          system.out.println(listofarrays.size());     system.out.println(listofarrays.get(0).size()); } 

my print statements give me right size of 96 arraylists empty. if remove temp.clear() consist of 28800 integers.

i need 96 * 300 different arraylists in arraylist.

for (int = 0; < list.size(); i++) {     integer arrayint = list.get(i);     temp.add(arrayint);      if (temp.size() % 300 == 0) {         listofarrays.add(temp);         temp = new arraylist<>();     } } 

dont use primitive int while retrieving element list. because unnecessarily cause unboxing , autoboxing again.

rather relying on list.size() % 300 == 0, should change logic also.

you can use arraylist method sublist.