[TIL][링크] 자바 리스트 stream split 처리 - groupingBy

Java8 Collectors groupingBy

Map<Integer, List<Integer>> groups = testList.stream().collect(Collectors.groupingBy(i -> i / 3));
List<List<Integer>> listByCollectors = new ArrayList<>(groups.values());

//will be..
listByCollectors = {ArrayList@1058}  size = 4
 0 = {ArrayList@1093}  size = 3
 1 = {ArrayList@1094}  size = 3
 2 = {ArrayList@1095}  size = 3
 3 = {ArrayList@1096}  size = 1

출처: https://jinseongsoft.tistory.com/312 [진성 소프트]