@Override
    public SortedSet<K> keySet() {
      SortedSet<K> result = sortedKeySet;
      return (result == null) ? sortedKeySet = createKeySet() : result;
    }

    @Override
    SortedSet<K> createKeySet() {
      return new SortedKeySet(sortedMap());
    }
  }

  private final class NavigableAsMap extends SortedAsMap implements NavigableMap<K, Collection<V>> {

  ImmutableSet<Entry<K, V>> createEntrySet() {
    return isEmpty()
        ? ImmutableSet.of()
        : new ImmutableMapEntrySet.RegularEntrySet<K, V>(this, entries);
  }

  @Override
  ImmutableSet<K> createKeySet() {
    return new ImmutableMapKeySet<>(this);
  }

  @Override
  public void forEach(BiConsumer<? super K, ? super V> action) {
    checkNotNull(action);
    for (Entry<K, V> entry : entries) {

  @Override
  public ImmutableSortedSet<K> keySet() {
    ImmutableSortedSet<K> ks = keySet;
    return (ks == null) ? (keySet = createKeySet()) : ks;
  }

  @Override
  ImmutableSortedSet<K> createKeySet() {
    // the keySet() of the delegate is only a Set and TreeMap.navigatableKeySet
    // is not available in GWT yet.  To keep the code simple and code size more,

      }
    }
  }

  @LazyInit private transient @Nullable Set<K> keySetView;

  @Override
  public Set<K> keySet() {
    return (keySetView == null) ? keySetView = createKeySet() : keySetView;
  }

  Set<K> createKeySet() {
    return new KeySetView();
  }

  @WeakOuter
  class KeySetView extends Maps.KeySet<K, V> {
    KeySetView() {
      super(CompactHashMap.this);
    }

        return Spliterators.spliterator(this, Spliterator.ORDERED | Spliterator.DISTINCT);
      }
    }
    return new EntrySetImpl();
  }

  @Override
  Set<K> createKeySet() {
    @WeakOuter
    final class KeySetImpl extends KeySetView {
      @Override
      public @Nullable Object[] toArray() {
        return ObjectArrays.toArrayImpl(this);
      }

      @Override

      }

      @Override
      public ListIterator<V> listIterator(int index) {
        return new ValueForKeyIterator(key, index);
      }
    };
  }

  @Override
  Set<K> createKeySet() {
    @WeakOuter
    final class KeySetImpl extends Sets.ImprovedAbstractSet<K> {
      @Override
      public int size() {
        return keyToKeyList.size();
      }

      @Override

   * appear in this multimap.
   */
  @Override
  public ImmutableSet<K> keySet() {
    return map.keySet();
  }

  @Override
  Set<K> createKeySet() {
    throw new AssertionError("unreachable");
  }

  /**
   * Returns an immutable map that associates each key with its corresponding values in the

      }
    }
  }

  @LazyInit private transient @Nullable Set<K> keySetView;

  @Override
  public Set<K> keySet() {
    return (keySetView == null) ? keySetView = createKeySet() : keySetView;
  }

  Set<K> createKeySet() {
    return new KeySetView();
  }

  @WeakOuter
  private final class KeySetView extends AbstractSet<K> {
    @Override
    public int size() {

   * appear in this multimap.
   */
  @Override
  public ImmutableSet<K> keySet() {
    return map.keySet();
  }

  @Override
  Set<K> createKeySet() {
    throw new AssertionError("unreachable");
  }

  /**
   * Returns an immutable map that associates each key with its corresponding values in the