*/
  @Override
  Iterator<E> iterator();

  /**
   * Returns a descending view of this multiset. Modifications made to either map will be reflected
   * in the other.
   */
  SortedMultiset<E> descendingMultiset();

  /**
   * Returns a view of this multiset restricted to the elements less than {@code upperBound},
   * optionally including {@code upperBound} itself. The returned multiset is a view of this

  public abstract ImmutableSortedSet<E> elementSet();

  @LazyInit transient @Nullable ImmutableSortedMultiset<E> descendingMultiset;

  @Override
  public ImmutableSortedMultiset<E> descendingMultiset() {
    ImmutableSortedMultiset<E> result = descendingMultiset;
    if (result == null) {
      return descendingMultiset =
          this.isEmpty()
              ? emptyMultiset(Ordering.from(comparator()).reverse())

            new ForwardingTestMultisetGenerator<E>(delegate) {
              @Override
              public SortedMultiset<E> create(Object... entries) {
                return ((SortedMultiset<E>) super.create(entries)).descendingMultiset();
              }

              @Override
              public Iterable<E> order(List<E> insertionOrder) {
                return ImmutableList.copyOf(super.order(insertionOrder)).reverse();
              }

            new ForwardingTestMultisetGenerator<E>(delegate) {
              @Override
              public SortedMultiset<E> create(Object... entries) {
                return ((SortedMultiset<E>) super.create(entries)).descendingMultiset();
              }

              @Override
              public Iterable<E> order(List<E> insertionOrder) {
                return ImmutableList.copyOf(super.order(insertionOrder)).reverse();
              }

    List<Entry<E>> ascending = new ArrayList<>();
    Iterators.addAll(ascending, sortedMultiset.entrySet().iterator());
    List<Entry<E>> descending = new ArrayList<>();
    Iterators.addAll(descending, sortedMultiset.descendingMultiset().entrySet().iterator());
    Collections.reverse(descending);
    assertEquals(ascending, descending);
  }

  void expectAddFailure(SortedMultiset<E> multiset, Entry<E> entry) {
    try {

    List<Entry<E>> ascending = new ArrayList<>();
    Iterators.addAll(ascending, sortedMultiset.entrySet().iterator());
    List<Entry<E>> descending = new ArrayList<>();
    Iterators.addAll(descending, sortedMultiset.descendingMultiset().entrySet().iterator());
    Collections.reverse(descending);
    assertEquals(ascending, descending);
  }

  void expectAddFailure(SortedMultiset<E> multiset, Entry<E> entry) {
    try {