Java ArrayList.removeAll(), but for indices

Question

Is there a way to do something like this:

ArrayList<String>.removeAll(ArrayList<Integer>)

With the ArrayList<Integer> being the indices that I want deleted. I know that I could iterate through the indices list and use remove(index), but I was wondering if there is a one-command way of doing so.

I know how to put this iteration into one line, my question is, if there is a way implemented by oracle.

Answer 1

You can use a Stream to iterate through the indices to remove. However, take care to remove the highest index first, to avoid shifting other elements to remove out of position.

public void removeIndices(List<String> strings, List<Integer> indices)
{
     indices.stream()
         .sorted(Comparator.reverseOrder())
         .forEach(strings::remove);
}

For removing from a list of Strings this will work, calling the proper remove(int) method. If you were to try this on a List<Integer>, then you will have to avoid calling remove(E) by calling .mapToInt(Integer::intValue) before calling forEach.