ImmutableSetMultimap<K, V> result = multimapView;
    return (result == null)
        ? (multimapView =
            new ImmutableSetMultimap<K, V>(new MapViewOfValuesAsSingletonSets(), size(), null))
        : result;
  }

  final class MapViewOfValuesAsSingletonSets extends IteratorBasedImmutableMap<K, ImmutableSet<V>> {

    @Override
    public int size() {
      return ImmutableMap.this.size();
    }

    return (result == null)
        ? (multimapView =
            new ImmutableSetMultimap<>(new MapViewOfValuesAsSingletonSets(), size(), null))
        : result;
  }

  @WeakOuter
  private final class MapViewOfValuesAsSingletonSets
      extends IteratorBasedImmutableMap<K, ImmutableSet<V>> {

    @Override
    public int size() {

    return (result == null)
        ? (multimapView =
            new ImmutableSetMultimap<>(new MapViewOfValuesAsSingletonSets(), size(), null))
        : result;
  }

  @WeakOuter
  private final class MapViewOfValuesAsSingletonSets
      extends IteratorBasedImmutableMap<K, ImmutableSet<V>> {

    @Override
    public int size() {