//刪除重復元素，不保持順序
List<String> NotList = new ArrayList();
NotList.add("1");
NotList.add("1");
NotList.add("2");
NotList.add("2");
NotList.add("3");
NotList.add("4");

NotList = new ArrayList<>(new HashSet<>(NotList));

for (int i=0;i<NotList.size();i++){
        printlns(
 
"NotList["+ i +"] = "+NotList.get(i));
    }

 /**
     * 刪除重復元素，保持順序
     */

//set
Set set = new HashSet();

//定義NotList 存儲用
List NotList = new ArrayList();

//排序用
List newNotList = new ArrayList();

NotList.add("1");
NotList.add("1");
NotList.add("2");
NotList.add("3");
NotList.add(
 
"4");

   for (Iterator iter =NotList.iterator();iter.hasNext();){
       Object element = iter.next();
       if(set.add(element)){
           newNotList.add(element);
       }
    }     
   NotList.clear();//清空
   NotList.addAll(newNotList);//添加

List去除重復數據，排序