} catch (IllegalArgumentException e) {
      return emptySet(comparator());
    }
  }

  public ImmutableSortedSet<E> tailSet(E fromElement, boolean inclusive) {
    checkNotNull(fromElement);
    if (!inclusive) {
      E tmp = higher(fromElement);
      if (tmp == null) {
        return emptySet(comparator());
      }
      fromElement = tmp;
    }

      Comparator<? super E> comparator) {
    return CollectCollectors.toImmutableSortedSet(comparator);
  }

  static <E> RegularImmutableSortedSet<E> emptySet(Comparator<? super E> comparator) {
    if (Ordering.natural().equals(comparator)) {
      @SuppressWarnings("unchecked") // The natural-ordered empty set supports all types.
      RegularImmutableSortedSet<E> result =

      Comparator<? super E> comparator) {
    return CollectCollectors.toImmutableSortedSet(comparator);
  }

  static <E> RegularImmutableSortedSet<E> emptySet(Comparator<? super E> comparator) {
    if (Ordering.natural().equals(comparator)) {
      @SuppressWarnings("unchecked") // The natural-ordered empty set supports all types.
      RegularImmutableSortedSet<E> result =