final class ValueIterator extends HashIterator<V> {

    @Override
    public V next() {
      return nextEntry().getValue();
    }
  }

  /**
   * Custom Entry class used by EntryIterator.next(), that relays setValue changes to the underlying
   * map.
   */
  final class WriteThroughEntry extends AbstractMapEntry<K, V> {
    final K key; // non-null
    V value; // non-null

  final class ValueIterator extends HashIterator<V> {

    @Override
    public V next() {
      return nextEntry().getValue();
    }
  }

  /**
   * Custom Entry class used by EntryIterator.next(), that relays setValue changes to the underlying
   * map.
   */
  final class WriteThroughEntry extends AbstractMapEntry<K, V> {
    final K key; // non-null
    V value; // non-null

    }

    @Override
    Multiset<K> createKeys() {
      return new Multimaps.Keys<K, V>(this);
    }

    @Override
    Iterator<Entry<K, V>> entryIterator() {
      return map.entrySet().iterator();
    }

    @Override
    Map<K, Collection<V>> createAsMap() {
      return new AsMap<>(this);
    }

    @Override