* elements.
   *
   * @param distinctElements the expected number of distinct elements
   * @throws IllegalArgumentException if {@code distinctElements} is negative
   */
  public static <E extends @Nullable Object> HashMultiset<E> create(int distinctElements) {
    return new HashMultiset<>(distinctElements);
  }

  /**

   * elements.
   *
   * @param distinctElements the expected number of distinct elements
   * @throws IllegalArgumentException if {@code distinctElements} is negative
   */
  public static <E extends @Nullable Object> HashMultiset<E> create(int distinctElements) {
    return new HashMultiset<>(distinctElements);
  }

  /**

    size += count - oldCount;
    if (oldCount == 0 && count > 0) {
      distinctElements++;
    } else if (oldCount > 0 && count == 0) {
      distinctElements--;
    }
    return oldCount;
  }

  @Override
  public void clear() {
    Arrays.fill(counts, 0);
    size = 0;
    distinctElements = 0;
  }

  abstract class Itr<T> implements Iterator<T> {
    int index = 0;

   * elements.
   *
   * @param distinctElements the expected number of distinct elements
   * @throws IllegalArgumentException if {@code distinctElements} is negative
   */
  public static <E extends @Nullable Object> LinkedHashMultiset<E> create(int distinctElements) {
    return new LinkedHashMultiset<>(distinctElements);
  }

  /**

   * elements.
   *
   * @param distinctElements the expected number of distinct elements
   * @throws IllegalArgumentException if {@code distinctElements} is negative
   */
  public static <E extends @Nullable Object> LinkedHashMultiset<E> create(int distinctElements) {
    return new LinkedHashMultiset<>(distinctElements);
  }

  /**

    size += count - oldCount;
    if (oldCount == 0 && count > 0) {
      distinctElements++;
    } else if (oldCount > 0 && count == 0) {
      distinctElements--;
    }
    return oldCount;
  }

  @Override
  public void clear() {
    Arrays.fill(counts, 0);
    size = 0;
    distinctElements = 0;
  }

  abstract class Itr<T> implements Iterator<T> {
    int index = 0;

    implements Serializable {

  transient ObjectCountHashMap<E> backingMap;
  transient long size;

  AbstractMapBasedMultiset(int distinctElements) {
    backingMap = newBackingMap(distinctElements);
  }

  abstract ObjectCountHashMap<E> newBackingMap(int distinctElements);

  @Override
  public final int count(@Nullable Object element) {
    return backingMap.get(element);
  }

   */
  static <E extends @Nullable Object> void populateMultiset(
      Multiset<E> multiset, ObjectInputStream stream) throws IOException, ClassNotFoundException {
    int distinctElements = stream.readInt();
    populateMultiset(multiset, stream, distinctElements);
  }

  /**
   * Populates a multiset by reading an input stream, as part of deserialization. See {@link
   * #writeMultiset} for the data format.
   */

   */
  static <E extends @Nullable Object> void populateMultiset(
      Multiset<E> multiset, ObjectInputStream stream) throws IOException, ClassNotFoundException {
    int distinctElements = stream.readInt();
    populateMultiset(multiset, stream, distinctElements);
  }

  /**
   * Populates a multiset by reading an input stream, as part of deserialization. See {@link
   * #writeMultiset} for the data format.
   */

      return entryIterator();
    }

    @Override
    public int size() {
      return distinctElements();
    }
  }

  Set<Entry<E>> createEntrySet() {
    return new EntrySet();
  }

  abstract Iterator<Entry<E>> entryIterator();

  abstract int distinctElements();

  // Object methods

  /**
   * {@inheritDoc}
   *