* Implementation of {@link Multimaps#filterKeys(Multimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
class FilteredKeyMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimap<K, V> implements FilteredMultimap<K, V> {
  final Multimap<K, V> unfiltered;
  final Predicate<? super K> keyPredicate;

  FilteredKeyMultimap(Multimap<K, V> unfiltered, Predicate<? super K> keyPredicate) {

 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
@SuppressWarnings("WrongCommentType") // false positive
public class LinkedListMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimap<K, V> implements ListMultimap<K, V>, Serializable {
  /*
   * Order is maintained using a linked list containing all key-value pairs. In
   * addition, a series of disjoint linked lists of "siblings", each containing

 * @author Louis Wasserman
 */
@GwtCompatible
@SuppressWarnings("WrongCommentType") // false positive
abstract class AbstractMapBasedMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimap<K, V> implements Serializable {
  /*
   * Here's an outline of the overall design.
   *
   * The map variable contains the collection of values associated with each

    return new MapMultimap<>(map);
  }

  /**
   * @see Multimaps#forMap
   */
  private static final class MapMultimap<K extends @Nullable Object, V extends @Nullable Object>
      extends AbstractMultimap<K, V> implements SetMultimap<K, V>, Serializable {
    final Map<K, V> map;

    MapMultimap(Map<K, V> map) {
      this.map = checkNotNull(map);
    }

    @Override
    public int size() {