this.factory = checkNotNull(factory);
    }

    @Override
    Set<K> createKeySet() {
      return createMaybeNavigableKeySet();
    }

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

    @Override
    protected Collection<V> createCollection() {
      return factory.get();
    }

    @Override

      this.factory = checkNotNull(factory);
    }

    @Override
    Set<K> createKeySet() {
      return createMaybeNavigableKeySet();
    }

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

    @Override
    protected Collection<V> createCollection() {
      return factory.get();
    }

    @Override

   */
  @Override
  @SuppressWarnings("unchecked") // a widening cast
  public ImmutableMap<K, Collection<V>> asMap() {
    return (ImmutableMap) map;
  }

  @Override
  Map<K, Collection<V>> createAsMap() {
    throw new AssertionError("should never be called");
  }

  /** Returns an immutable collection of all key-value pairs in the multimap. */
  @Override
  public ImmutableCollection<Entry<K, V>> entries() {