}

  @Override
  public NavigableSet<E> tailSet(@ParametricNullness E fromElement, boolean inclusive) {
    return delegate().tailSet(fromElement, inclusive);
  }

  /**
   * A sensible definition of {@link #tailSet(Object)} in terms of the {@link #tailSet(Object,
   * boolean)} method. If you override {@link #tailSet(Object, boolean)}, you may wish to override
   * {@link #tailSet(Object)} to forward to this implementation.
   */

      return new FilteredSortedSet<>(((SortedSet<E>) unfiltered).headSet(toElement), predicate);
    }

    @Override
    public SortedSet<E> tailSet(@ParametricNullness E fromElement) {
      return new FilteredSortedSet<>(((SortedSet<E>) unfiltered).tailSet(fromElement), predicate);
    }

    @Override
    @ParametricNullness
    public E first() {

    return delegate().subSet(fromElement, toElement);
  }

  @Override
  public SortedSet<E> tailSet(@ParametricNullness E fromElement) {
    return delegate().tailSet(fromElement);
  }

  /**
   * A sensible definition of {@link #contains} in terms of the {@code first()} method of {@link
   * #tailSet}. If you override {@link #tailSet}, you may wish to override {@link #contains} to
   * forward to this implementation.
   *

      return emptySet(comparator());
    }
    return tailSet(fromElement, fromInclusive).headSet(toElement, toInclusive);
  }

  public ImmutableSortedSet<E> tailSet(E fromElement) {
    checkNotNull(fromElement);
    try {
      return unsafeDelegateSortedSet(sortedDelegate.tailSet(fromElement), true);
    } catch (IllegalArgumentException e) {
      return emptySet(comparator());

      if (from == Bound.NO_BOUND && to == Bound.INCLUSIVE) {
        return set.headSet(lastInclusive, true);
      } else if (from == Bound.EXCLUSIVE && to == Bound.NO_BOUND) {
        return set.tailSet(firstExclusive, false);
      } else if (from == Bound.EXCLUSIVE && to == Bound.EXCLUSIVE) {
        return set.subSet(firstExclusive, false, lastExclusive, false);
      } else if (from == Bound.EXCLUSIVE && to == Bound.INCLUSIVE) {

    @Override
    protected SortedSet<String> create(String[] elements) {
      List<String> list = Lists.newArrayList(elements);
      list.add("\0");
      return ImmutableSortedSet.copyOf(list).tailSet("\0\0");
    }
  }

  public static class ImmutableSortedSetSubsetGenerator extends TestStringSortedSetGenerator {
    @Override
    protected SortedSet<String> create(String[] elements) {

      return new FilteredSortedSet<>(((SortedSet<E>) unfiltered).headSet(toElement), predicate);
    }

    @Override
    public SortedSet<E> tailSet(@ParametricNullness E fromElement) {
      return new FilteredSortedSet<>(((SortedSet<E>) unfiltered).tailSet(fromElement), predicate);
    }

    @Override
    @ParametricNullness
    public E first() {

    return subSetImpl(fromElement, fromInclusive, toElement, toInclusive);
  }

  @Override
  public ContiguousSet<C> tailSet(C fromElement) {
    return tailSetImpl(checkNotNull(fromElement), true);
  }

  /** @since 12.0 */
  @GwtIncompatible // NavigableSet
  @Override
  public ContiguousSet<C> tailSet(C fromElement, boolean inclusive) {
    return tailSetImpl(checkNotNull(fromElement), inclusive);
  }

  /*

          sortedMap().subMap(fromElement, fromInclusive, toElement, toInclusive));
    }

    @Override
    public NavigableSet<K> tailSet(@ParametricNullness K fromElement) {
      return tailSet(fromElement, true);
    }

    @Override
    public NavigableSet<K> tailSet(@ParametricNullness K fromElement, boolean inclusive) {
      return new NavigableKeySet(sortedMap().tailMap(fromElement, inclusive));
    }
  }

  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return forward.descendingIterator();
  }

  @Override
  ImmutableSortedSet<E> headSetImpl(E toElement, boolean inclusive) {
    return forward.tailSet(toElement, inclusive).descendingSet();
  }

  @Override
  ImmutableSortedSet<E> subSetImpl(
      E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {