* A sensible implementation of {@link SortedMultiset#elementSet} in terms of the following
   * methods: {@link SortedMultiset#clear}, {@link SortedMultiset#comparator}, {@link
   * SortedMultiset#contains}, {@link SortedMultiset#containsAll}, {@link SortedMultiset#count},
   * {@link SortedMultiset#firstEntry} {@link SortedMultiset#headMultiset}, {@link
   * SortedMultiset#isEmpty}, {@link SortedMultiset#lastEntry}, {@link SortedMultiset#subMultiset},

            return parent.add(e);
        }

        public boolean remove(final Object o) {
            return parent.remove(o);
        }

        public boolean containsAll(final Collection<?> c) {
            return parent.containsAll(c);
        }

        public boolean addAll(final Collection<? extends E> c) {
            return parent.addAll(c);
        }

            return parent.add(e);
        }

        public boolean remove(final Object o) {
            return parent.remove(o);
        }

        public boolean containsAll(final Collection<?> c) {
            return parent.containsAll(c);
        }

        public boolean addAll(final Collection<? extends E> c) {
            return parent.addAll(c);
        }

  /**
   * Returns {@code true} if this multiset contains at least one occurrence of each element in the
   * specified collection.
   *
   * <p>This method refines {@link Collection#containsAll} to further specify that it <b>may not</b>
   * throw an exception in response to any of {@code elements} being null or of the wrong type.
   *

    }

    @Override
    public boolean contains(@CheckForNull Object o) {
      return multiset().contains(o);
    }

    @Override
    public boolean containsAll(Collection<?> c) {
      return multiset().containsAll(c);
    }

    @Override
    public boolean isEmpty() {
      return multiset().isEmpty();
    }

    @Override
    public abstract Iterator<E> iterator();

    }

    @Override
    public boolean contains(@CheckForNull Object o) {
      return multiset().contains(o);
    }

    @Override
    public boolean containsAll(Collection<?> c) {
      return multiset().containsAll(c);
    }

    @Override
    public boolean isEmpty() {
      return multiset().isEmpty();
    }

    @Override
    public abstract Iterator<E> iterator();

  /**
   * Returns {@code true} if this multiset contains at least one occurrence of each element in the
   * specified collection.
   *
   * <p>This method refines {@link Collection#containsAll} to further specify that it <b>may not</b>
   * throw an exception in response to any of {@code elements} being null or of the wrong type.
   *

    try {
      requirements = FeatureUtil.getTesterRequirements(method);
    } catch (ConflictingRequirementsException e) {
      throw new RuntimeException(e);
    }
    if (!features.containsAll(requirements.getPresentFeatures())) {
      if (logger.isLoggable(FINER)) {
        Set<Feature<?>> missingFeatures = copyToSet(requirements.getPresentFeatures());
        missingFeatures.removeAll(features);

  }

  /**
   * A sensible implementation of {@link Multiset#elementSet} in terms of the following methods:
   * {@link ForwardingMultiset#clear}, {@link ForwardingMultiset#contains}, {@link
   * ForwardingMultiset#containsAll}, {@link ForwardingMultiset#count}, {@link
   * ForwardingMultiset#isEmpty}, the {@link Set#size} and {@link Set#iterator} methods of {@link

    ImmutableSortedSet<Integer> asSet = RANGE_SET_ONE.asSet(DiscreteDomain.integers());
    assertEquals(expectedSet, asSet);
    assertThat(asSet).containsExactlyElementsIn(expectedSet).inOrder();
    assertTrue(asSet.containsAll(expectedSet));
    SerializableTester.reserializeAndAssert(asSet);
  }

  public void testAsSetHeadSet() {
    ImmutableSortedSet<Integer> expectedSet = ImmutableSortedSet.of(2, 3, 4, 8, 9, 16, 17);