*/
  @WeakOuter
  class WrappedCollection extends AbstractCollection<V> {
    @ParametricNullness final K key;
    Collection<V> delegate;
    final @Nullable WrappedCollection ancestor;
    final @Nullable Collection<V> ancestorDelegate;

    WrappedCollection(
        @ParametricNullness K key, Collection<V> delegate, @Nullable WrappedCollection ancestor) {
      this.key = key;

        return new WrappedSortedSet(key, (SortedSet<V>) collection, null);
      } else if (collection instanceof Set) {
        return new WrappedSet(key, (Set<V>) collection);
      } else {
        return new WrappedCollection(key, collection, null);
      }
    }

    // can't use Serialization writeMultimap and populateMultimap methods since
    // there's no way to generate the empty backing map.

    /**

        return new WrappedSortedSet(key, (SortedSet<V>) collection, null);
      } else if (collection instanceof Set) {
        return new WrappedSet(key, (Set<V>) collection);
      } else {
        return new WrappedCollection(key, collection, null);
      }
    }

    // can't use Serialization writeMultimap and populateMultimap methods since
    // there's no way to generate the empty backing map.

    /**