Set的5种遍历方式

public static void main(String[] args) {
    List<Integer> list = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12));
    Set<Integer> sets = new HashSet<>(16);
    sets.addAll(list);
    //foreach遍历
    System.out.println("\n遍历1： foreach:");
    for (Integer i : sets) {
        System.out.print(i + " ");
    }
    //iterator遍历
    System.out.println("\n遍历2： iterator:");
    Iterator<Integer> iterator = sets.iterator();
    while (iterator.hasNext()) {
        System.out.print(iterator.next() + " ");
    }
    //stream流遍历
    System.out.println("\n遍历3： stream流");
    sets.forEach(s -> System.out.print(s + " "));
    //for循环遍历
    System.out.println("\n遍历4：for循环");
    Iterator<Integer> iterator2 = sets.iterator();
    for (int i = 0; i < sets.size(); i++) {
        System.out.print(iterator2.next() + " ");
    }
  // forEachRemaining:底层实现while (hasNext()) action.accept(next());  
  System.out.println("\n遍历5：forEachRemaining");
    sets.iterator().forEachRemaining(s -> System.out.print(s + " "));
}