去掉一个集合中包含的另一个集合的数据

一、将其转化成HashSet进行操作

            LinkedList<Question> veirfyingList = questionService.getVeirfying(cityCode);
            LinkedList<Question> verifiedList = questionService.getVerifiedQuestion(uid, cityCode);
            HashSet h1 = new HashSet(veirfyingList);
            HashSet h2 = new HashSet(verifiedList);
            h1.removeAll(h2);
            veirfyingList.clear();
            veirfyingList.addAll(h1);

二、利用CollectionUtils工具类来操作

@Test
public void testSubtract(){
    String[] arrayA = new String[] { "A", "B", "C", "D", "E", "F" };  
    String[] arrayB = new String[] { "B", "D", "F", "G", "H", "K" };
    List<String> listA = Arrays.asList(arrayA);
    List<String> listB = Arrays.asList(arrayB);
    //arrayA扣除arrayB
    System.out.println(ArrayUtils.toString(CollectionUtils.subtract(listA, listB)));
    //[A, C, E]

}

附上第二种的CollectionUtils的依赖

       
            commons-collections
            commons-collections
            3.2.2
        

补： 其他方法还可用stream流 但第二种是最方便的方法（目前公司项目我就是用此方法去除的相同元素 即求得差集）