*
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
abstract class TransformedIterator<F extends @Nullable Object, T extends @Nullable Object>
    implements Iterator<T> {
  final Iterator<? extends F> backingIterator;

  TransformedIterator(Iterator<? extends F> backingIterator) {
    this.backingIterator = checkNotNull(backingIterator);
  }

  @ParametricNullness

 *
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
abstract class TransformedListIterator<F extends @Nullable Object, T extends @Nullable Object>
    extends TransformedIterator<F, T> implements ListIterator<T> {
  TransformedListIterator(ListIterator<? extends F> backingIterator) {
    super(backingIterator);
  }

  private ListIterator<? extends F> backingIterator() {

    return (result == null) ? values = createValues() : result;
  }

  Collection<V> createValues() {
    return new Values();
  }

  Iterator<V> valuesIterator() {
    return new TransformedIterator<Cell<R, C, V>, V>(cellSet().iterator()) {
      @Override
      @ParametricNullness
      V transform(Cell<R, C, V> cell) {
        return cell.getValue();
      }
    };
  }

  @WeakOuter

    return (result == null) ? values = createValues() : result;
  }

  Collection<V> createValues() {
    return new Values();
  }

  Iterator<V> valuesIterator() {
    return new TransformedIterator<Cell<R, C, V>, V>(cellSet().iterator()) {
      @Override
      @ParametricNullness
      V transform(Cell<R, C, V> cell) {
        return cell.getValue();
      }
    };
  }

        return MutableClassToInstanceMap.this.delegate().entrySet();
      }

      @Override
      public Iterator<Entry<Class<? extends @NonNull B>, B>> iterator() {
        return new TransformedIterator<
            Entry<Class<? extends @NonNull B>, B>, Entry<Class<? extends @NonNull B>, B>>(
            delegate().iterator()) {
          @Override
          Entry<Class<? extends @NonNull B>, B> transform(

      super(delegate, mutex);
    }

    @Override
    public Iterator<Map.Entry<K, Collection<V>>> iterator() {
      // Must be manually synchronized.
      return new TransformedIterator<Map.Entry<K, Collection<V>>, Map.Entry<K, Collection<V>>>(
          super.iterator()) {
        @Override
        Map.Entry<K, Collection<V>> transform(final Map.Entry<K, Collection<V>> entry) {

      return true;
    } else {
      return false;
    }
  }

  static <E extends @Nullable Object> Iterator<E> elementIterator(
      Iterator<Entry<E>> entryIterator) {
    return new TransformedIterator<Entry<E>, E>(entryIterator) {
      @Override
      @ParametricNullness
      E transform(Entry<E> entry) {
        return entry.getElement();
      }
    };
  }

    return (Function) EntryFunction.VALUE;
  }

  static <K extends @Nullable Object, V extends @Nullable Object> Iterator<K> keyIterator(
      Iterator<Entry<K, V>> entryIterator) {
    return new TransformedIterator<Entry<K, V>, K>(entryIterator) {
      @Override
      @ParametricNullness
      K transform(Entry<K, V> entry) {
        return entry.getKey();
      }
    };
  }

  public static <F extends @Nullable Object, T extends @Nullable Object> Iterator<T> transform(
      Iterator<F> fromIterator, Function<? super F, ? extends T> function) {
    checkNotNull(function);
    return new TransformedIterator<F, T>(fromIterator) {
      @ParametricNullness
      @Override
      T transform(@ParametricNullness F from) {
        return function.apply(from);
      }
    };
  }

  /**

  public static <F extends @Nullable Object, T extends @Nullable Object> Iterator<T> transform(
      Iterator<F> fromIterator, Function<? super F, ? extends T> function) {
    checkNotNull(function);
    return new TransformedIterator<F, T>(fromIterator) {
      @ParametricNullness
      @Override
      T transform(@ParametricNullness F from) {
        return function.apply(from);
      }
    };
  }

  /**