@Nullable Segment<K, V, E, S> currentSegment;
    @Nullable AtomicReferenceArray<E> currentTable;
    @Nullable E nextEntry;
    @Nullable WriteThroughEntry nextExternal;
    @Nullable WriteThroughEntry lastReturned;

    HashIterator() {
      nextSegmentIndex = segments.length - 1;
      nextTableIndex = -1;
      advance();
    }

    @Override
    public abstract T next();

 *
 * @author Jared Levy
 * @since 2.0
 */
@DoNotMock("Use ImmutableMultimap, HashMultimap, or another implementation")
@GwtCompatible
public interface Multimap<K extends @Nullable Object, V extends @Nullable Object> {
  // Query Operations

  /**
   * Returns the number of key-value pairs in this multimap.
   *

     * in the value bucket (or vice versa).
     */
    private final transient @Nullable ImmutableMapEntry<K, V> nextInKeyBucket;

    NonTerminalImmutableMapEntry(
        K key, V value, @Nullable ImmutableMapEntry<K, V> nextInKeyBucket) {
      super(key, value);
      this.nextInKeyBucket = nextInKeyBucket;
    }

    @Override
    final @Nullable ImmutableMapEntry<K, V> getNextInKeyBucket() {
      return nextInKeyBucket;

    delegate().clear();
  }

  @Override
  public boolean containsEntry(@Nullable Object key, @Nullable Object value) {
    return delegate().containsEntry(key, value);
  }

  @Override
  public boolean containsKey(@Nullable Object key) {
    return delegate().containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return delegate().containsValue(value);
  }

  @Override

    delegate().clear();
  }

  @Override
  public boolean containsEntry(@Nullable Object key, @Nullable Object value) {
    return delegate().containsEntry(key, value);
  }

  @Override
  public boolean containsKey(@Nullable Object key) {
    return delegate().containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return delegate().containsValue(value);
  }

  @Override

    return size() == 0;
  }

  @Override
  public boolean containsKey(@Nullable Object key) {
    return get(key) != null;
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return values().contains(value);
  }

  // Overriding to mark it Nullable
  @Override
  public abstract @Nullable V get(@Nullable Object key);

  /**
   * @since 21.0 (but only since 23.5 in the Android <a

  }

  public void testNullFriendlyTransform() {
    Iterator<@Nullable Integer> input = Arrays.<@Nullable Integer>asList(1, 2, null, 3).iterator();
    Iterator<String> result =
        Iterators.transform(
            input,
            new Function<@Nullable Integer, String>() {
              @Override
              public String apply(@Nullable Integer from) {
                return String.valueOf(from);
              }

   */
  public static <F extends @Nullable Object, T extends @Nullable Object> Supplier<T> compose(
      Function<? super F, T> function, Supplier<F> supplier) {
    return new SupplierComposition<>(function, supplier);
  }

  private static final class SupplierComposition<
          F extends @Nullable Object, T extends @Nullable Object>
      implements Supplier<T>, Serializable {

    public @Nullable K floorKey(K key) {
      return standardFloorKey(key);
    }

    @Override
    public @Nullable Entry<K, V> ceilingEntry(K key) {
      return standardCeilingEntry(key);
    }

    @Override
    public @Nullable K ceilingKey(K key) {
      return standardCeilingKey(key);
    }

    @Override
    public @Nullable Entry<K, V> higherEntry(K key) {
      return standardHigherEntry(key);

 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
abstract class AbstractListMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapBasedMultimap<K, V> implements ListMultimap<K, V> {
  /**
   * Creates a new multimap that uses the provided map.
   *
   * @param map place to store the mapping from each key to its corresponding values
   */