检查两个List <int>的相同数字

List<Integer> list1 = Arrays.asList(1, 2, 3, 4, 5);
List<Integer> list2 = Arrays.asList(4, 5, 6, 7, 8);

HashSet<Integer> set1 = new HashSet<>(list1);
HashSet<Integer> set2 = new HashSet<>(list2);

set1.retainAll(set2); // 交集

System.out.println("相同的数字: " + set1);

List<Integer> list1 = Arrays.asList(1, 2, 3, 4, 5);
List<Integer> list2 = Arrays.asList(4, 5, 6, 7, 8);

List<Integer> commonNumbers = list1.stream()
        .filter(list2::contains)
        .collect(Collectors.toList());

System.out.println("相同的数字: " + commonNumbers);