private @NotNull IntList findAllFilteredElements(@NotNull String s) {
    IntList indices = new IntArrayList();
    String trimmed = s.trim();

    ListIterator<Object> iterator = getElementIterator(0);
    while (iterator.hasNext()) {
      Object element = iterator.next();
      if (isMatchingElement(element, trimmed)) {
        indices.add(iterator.previousIndex());
      }
    }
    return indices;
  }
private @NotNull IntList findAllFilteredElements(@NotNull String s)