Java8中List的排序

public void testListSort() {
List<Long> idList = new ArrayList<>();
idList.add(23L);
idList.add(22L);
idList.add(20L);
idList.add(21L);
System.out.println(idList);

//java8 before
idList.sort(new Comparator<Long>() {
@Override
public int compare(Long o1, Long o2) {

if (o1.longValue() < o2.longValue()) {
return -1;
} else if (o1.longValue() > o2.longValue()) {
return 1;
}
return 0;
}
});

System.out.println(idList);

//java8
List<Long> sortIdList = idList.stream().sorted(Long::compareTo).collect(Collectors.toList());
System.out.println(sortIdList);

//java8
List<Integer> integerList = Arrays.asList(0, 3, 2, 1);
Collections.sort(integerList, Integer::compareTo);
System.out.println(integerList);
}