* for the data format.
   */
  static <K extends @Nullable Object, V extends @Nullable Object> void populateMap(
      Map<K, V> map, ObjectInputStream stream) throws IOException, ClassNotFoundException {
    int size = stream.readInt();
    populateMap(map, stream, size);
  }

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

  }

  @GwtIncompatible
  @J2ktIncompatible
    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    int distinctElements = stream.readInt();
    setBackingMap(new LinkedHashMap<E, Count>());
    Serialization.populateMultiset(this, stream, distinctElements);
  }

  @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;

  }

  @GwtIncompatible
  @J2ktIncompatible
    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    int distinctElements = stream.readInt();
    backingMap = newBackingMap(ObjectCountHashMap.DEFAULT_SIZE);
    Serialization.populateMultiset(this, stream, distinctElements);
  }

    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    expectedValuesPerKey = DEFAULT_VALUES_PER_KEY;
    int distinctKeys = stream.readInt();
    Map<K, Collection<V>> map = new HashMap<>();
    setMap(map);
    Serialization.populateMultimap(this, stream, distinctKeys);
  }

  }

  @GwtIncompatible
  @J2ktIncompatible
    private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    int size = stream.readInt();
    init(16); // resist hostile attempts to allocate gratuitous heap
    Serialization.populateMap(this, stream, size);
  }

  // TODO(cpovirk): Should we have a serialVersionUID here?