public E floor(E element) {
    int index = headIndex(element, true) - 1;
    return (index == -1) ? null : elements.get(index);
  }

  @Override
  @CheckForNull
  public E ceiling(E element) {
    int index = tailIndex(element, true);
    return (index == size()) ? null : elements.get(index);
  }

  @Override
  @CheckForNull
  public E higher(E element) {
    int index = tailIndex(element, false);

  public void testHashCode_containingNull() {
    Collection<E> elements = getSampleElements(getNumElements() - 1);
    int expectedHashCode = 0;
    for (E element : elements) {
      expectedHashCode += ((element == null) ? 0 : element.hashCode());
    }

    elements.add(null);
    collection = getSubjectGenerator().create(elements.toArray());
    assertEquals(

    public abstract Builder<E> add(E element);

    @CanIgnoreReturnValue
    public Builder<E> add(E... elements) {
      checkNotNull(elements); // for GWT
      for (E element : elements) {
        add(checkNotNull(element));
      }
      return this;
    }

    @CanIgnoreReturnValue
    public Builder<E> addAll(Iterable<? extends E> elements) {
      checkNotNull(elements); // for GWT

    }

    @Override
    public boolean add(T element) {
      return standardAdd(element);
    }

    @Override
    public boolean addAll(Collection<? extends T> collection) {
      return standardAddAll(collection);
    }

    @Override
    public boolean addAll(int index, Collection<? extends T> elements) {
      return standardAddAll(index, elements);
    }

    @Override
    public void clear() {

   * ordering of the elements is used.
   */
  @Override
  Comparator<? super E> comparator();

  /**
   * Returns the entry of the first element in this multiset, or {@code null} if this multiset is
   * empty.
   */
  @CheckForNull
  Entry<E> firstEntry();

  /**
   * Returns the entry of the last element in this multiset, or {@code null} if this multiset is
   * empty.
   */

  @Override
  protected abstract List<E> delegate();

  @Override
  public void add(int index, @ParametricNullness E element) {
    delegate().add(index, element);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean addAll(int index, Collection<? extends E> elements) {
    return delegate().addAll(index, elements);
  }

  @Override
  @ParametricNullness
  public E get(int index) {
    return delegate().get(index);

  }

  protected void expectMissingKeys(K... elements) {
    for (K element : elements) {
      assertFalse("Should not contain key " + element, getMap().containsKey(element));
    }
  }

  protected void expectMissingValues(V... elements) {
    for (V element : elements) {
      assertFalse("Should not contain value " + element, getMap().containsValue(element));
    }
  }

        elements[i] = entry.getElement();
        counts[i] = entry.getCount();
        i++;
      }
    }

    Object readResolve() {
      ImmutableMultiset.Builder<Object> builder =
          new ImmutableMultiset.Builder<Object>(elements.length);
      for (int i = 0; i < elements.length; i++) {
        builder.addCopies(elements[i], counts[i]);
      }

    while (true) {
      if (to <= from + 1) {
        // Two or less elements left.
        if (to == from + 1 && array[to] < array[from]) {
          // Exactly two elements left.
          swap(array, from, to);
        }
        return array[k];
      } else {
        int midIndex = (from + to) >>> 1;
        // Choose the median of the elements at the from, to and mid indexes,

    while (true) {
      if (to <= from + 1) {
        // Two or less elements left.
        if (to == from + 1 && array[to] < array[from]) {
          // Exactly two elements left.
          swap(array, from, to);
        }
        return array[k];
      } else {
        int midIndex = (from + to) >>> 1;
        // Choose the median of the elements at the from, to and mid indexes,