* {@code ForwardingIterator}.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingIterator<T extends @Nullable Object> extends ForwardingObject
    implements Iterator<T> {

  /** Constructor for use by subclasses. */
  protected ForwardingIterator() {}

  @Override

 * {@code ForwardingIterator}.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingIterator<T extends @Nullable Object> extends ForwardingObject
    implements Iterator<T> {

  /** Constructor for use by subclasses. */
  protected ForwardingIterator() {}

  @Override

 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingListIterator<E extends @Nullable Object>
    extends ForwardingIterator<E> implements ListIterator<E> {

  /** Constructor for use by subclasses. */
  protected ForwardingListIterator() {}

  @Override
  protected abstract ListIterator<E> delegate();

  @Override

 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingListIterator<E extends @Nullable Object>
    extends ForwardingIterator<E> implements ListIterator<E> {

  /** Constructor for use by subclasses. */
  protected ForwardingListIterator() {}

  @Override
  protected abstract ListIterator<E> delegate();

  @Override

  }

  @Override
  Iterator<Entry<E>> entryIterator() {
    // AbstractIterator makes this fairly clean, but it doesn't support remove(). To support
    // remove(), we create an AbstractIterator, and then use ForwardingIterator to delegate to it.
    Iterator<Entry<E>> readOnlyIterator =
        new AbstractIterator<Entry<E>>() {
          private final Iterator<Map.Entry<E, AtomicInteger>> mapEntries =

  }

  @Override
  Iterator<Entry<E>> entryIterator() {
    // AbstractIterator makes this fairly clean, but it doesn't support remove(). To support
    // remove(), we create an AbstractIterator, and then use ForwardingIterator to delegate to it.
    Iterator<Entry<E>> readOnlyIterator =
        new AbstractIterator<Entry<E>>() {
          private final Iterator<Map.Entry<E, AtomicInteger>> mapEntries =