private static void removeFilesAcceptedByFilter(@NotNull Set<? extends File> files, @Nullable FileFilter filter) {
    if (filter != null) {
      for (final Iterator<? extends File> it = files.iterator(); it.hasNext();) {
        if (filter.accept(it.next())) {
          it.remove();
        }
      }
    }
  }
private static void removeFilesAcceptedByFilter(@NotNull Set<? extends File> files, @Nullable FileFilter filter)