private final SortedSet<String> delegate = Sets.newTreeSet(Ordering.natural());

    @Override
    protected SortedSet<String> delegate() {
      return delegate;
    }
  }

  private static class NonNavigableSortedMap extends ForwardingSortedMap<String, String> {

    private final SortedMap<String, String> delegate = new SafeTreeMap<>(Ordering.natural());

    @Override

    implements SortedMultiset<E> {
  private final Comparator<? super E> comparator;

  // needed for serialization
  @SuppressWarnings("unchecked")
  AbstractSortedMultiset() {
    this((Comparator) Ordering.natural());
  }

  AbstractSortedMultiset(Comparator<? super E> comparator) {
    this.comparator = checkNotNull(comparator);
  }

  @Override
  public NavigableSet<E> elementSet() {

  }

  protected abstract Set<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new

  @Parameters(name = "allowsSelfLoops={0}, allowsParallelEdges={1}, nodeOrder={2}, edgeOrder={3}")
  public static Collection<Object[]> parameters() {
    ElementOrder<?> naturalElementOrder = ElementOrder.sorted(Ordering.natural());

    return Arrays.asList(
        new Object[][] {
          {false, false, ElementOrder.insertion(), ElementOrder.insertion()},
          {true, false, ElementOrder.insertion(), ElementOrder.insertion()},

  @Parameters(name = "allowsSelfLoops={0}, allowsParallelEdges={1}, nodeOrder={2}, edgeOrder={3}")
  public static Collection<Object[]> parameters() {
    ElementOrder<?> naturalElementOrder = ElementOrder.sorted(Ordering.natural());

    return Arrays.asList(
        new Object[][] {
          {false, false, ElementOrder.insertion(), ElementOrder.insertion()},
          {true, false, ElementOrder.insertion(), ElementOrder.insertion()},

  @Parameters(name = "allowsSelfLoops={0}, allowsParallelEdges={1}, nodeOrder={2}, edgeOrder={3}")
  public static Collection<Object[]> parameters() {
    ElementOrder<?> naturalElementOrder = ElementOrder.sorted(Ordering.natural());

    return Arrays.asList(
        new Object[][] {
          {false, false, ElementOrder.insertion(), ElementOrder.insertion()},
          {true, false, ElementOrder.insertion(), ElementOrder.insertion()},

      if (Ordering.<C>natural().equals(comparator) || comparator == null) {
        return closed(set.first(), set.last());
      }
    }
    Iterator<C> valueIterator = values.iterator();
    C min = checkNotNull(valueIterator.next());
    C max = min;
    while (valueIterator.hasNext()) {
      C value = checkNotNull(valueIterator.next());
      min = Ordering.<C>natural().min(min, value);

    throw new InvalidObjectException("Use SerializedForm");
  }

  @GwtIncompatible // NavigableSet
  @Override
  ImmutableSortedSet<C> createDescendingSet() {
    return ImmutableSortedSet.emptySet(Ordering.<C>natural().reverse());
  }

    return new AnEnum[length];
  }

  @Override
  public final String[] createValueArray(int length) {
    return new String[length];
  }

  /** Returns the elements sorted in natural order. */
  @Override
  public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {
    return orderEntriesByKey(insertionOrder);
  }

  @Parameters(name = "allowsSelfLoops={0}, allowsParallelEdges={1}, nodeOrder={2}, edgeOrder={3}")
  public static Collection<Object[]> parameters() {
    ElementOrder<?> naturalElementOrder = ElementOrder.sorted(Ordering.natural());

    return Arrays.asList(
        new Object[][] {
          {false, false, ElementOrder.insertion(), ElementOrder.insertion()},
          {true, false, ElementOrder.insertion(), ElementOrder.insertion()},