卸下ArrayList中的多个元素 [英] Remove multiple elements from ArrayList

问题描述

我有一大堆的指标，我想这些指标从的ArrayList 删除元素。我不能做一个简单的序列删除（），因为元素也被删除后移秒。我该如何解决这个问题？

I have a bunch of indexes and I want to remove elements at these indexes from an ArrayList. I can't do a simple sequence of remove()s because the elements are shifted after each removal. How do I solve this?

推荐答案

按降序排列的索引，然后一个删除它们。如果你这样做，有没有办法删除会影响到你以后要删除的任何索引。

Sort the indices in descending order and then remove them one by one. If you do that, there's no way a remove will affect any indices that you later want to remove.

您如何对它们进行排序，将取决于你所使用存储索引的集合。如果它是一个列表，你可以这样做：

How you sort them will depend on the collection you are using to store the indices. If it's a list, you can do this:

List<Integer> indices;
Collections.sort(indices, new Comparator<Integer>() {
   public int compare(Integer a, Integer b) {
      //todo: handle null
      return b.compareTo(a);
   }
}

修改

@aioobe发现，我没能找到帮手。取而代之的是上述情况，你可以使用

Edit

@aioobe found the helper that I failed to find. Instead of the above, you can use

Collections.sort(indices, Collections.reverseOrder());

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