JAVA LIST去重

public static void main(String[] args) {
				List list = new ArrayList();
				list.add("123");
				list.add("456");
				list.add("789");
				list.add("456");
				list.add("456");
				Set temp = new HashSet();
				List newList = new ArrayList();
				Iterator<String> iterator = list.iterator();
				while(iterator.hasNext()){
					Object el = iterator.next();
					if(temp.add(el)) newList.add(el);
				}
				System.out.println(newList);
			}