* the given future (if available).
   */
  final void maybePropagateCancellationTo(@CheckForNull Future<?> related) {
    if (related != null & isCancelled()) {
      related.cancel(wasInterrupted());
    }
  }

  /** Releases all threads in the {@link #waiters} list, and clears the list. */
  private void releaseWaiters() {

    Set<List<Integer>> degenerate = Sets.cartesianProduct();
    checkHashCode(degenerate);

    checkHashCode(Sets.cartesianProduct(set(1, 2)));

    int num = Integer.MAX_VALUE / 3 * 2; // tickle overflow-related problems
    checkHashCode(Sets.cartesianProduct(set(1, 2, num)));

    Set<Integer> mt = emptySet();
    checkHashCode(Sets.cartesianProduct(mt, mt));
    checkHashCode(Sets.cartesianProduct(mt, set(num)));

   * {@link Predicate#apply}. Do not provide a predicate such as {@code
   * Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals. (See {@link
   * Iterables#filter(Iterable, Class)} for related functionality.)
   *
   * <p><b>Java 8+ users:</b> many use cases for this method are better addressed by {@link
   * java.util.stream.Stream#filter}. This method is not being deprecated, but we gently encourage

   * more convenient.
   *
   * <p>Builder instances can be reused - it is safe to call {@link #buildOrThrow} multiple times to
   * build multiple maps in series. Each map is a superset of the maps created before it.
   *
   * @since 2.0
   */
  public static class Builder<K, V> extends ImmutableMap.Builder<K, V> {
    private transient @Nullable Object[] keys;
    private transient @Nullable Object[] values;

 * backing collection and the mutex are serializable.
 *
 * <p>If {@code null} is passed as the {@code mutex} parameter to any of this class's top-level
 * methods or inner class constructors, the created object uses itself as the synchronization mutex.
 *
 * <p>This class should be used by other collection classes only.
 *
 * @author Mike Bostock
 * @author Jared Levy
 */
@GwtCompatible(emulated = true)

    /** Returns a freshly created segment, typed at the {@code S} type. */
    S newSegment(MapMakerInternalMap<K, V, E, S> map, int initialCapacity);

    /**
     * Returns a freshly created entry, typed at the {@code E} type, for the given {@code segment}.
     */
    E newEntry(S segment, K key, int hash, @CheckForNull E next);

    /**

   * transformation function.
   *
   * <p>The primary audience of this method is callers of {@code transform} who don't have a {@code
   * ListenableFuture} available and do not mind repeated, lazy function evaluation.
   *
   * @param input The future to transform
   * @param function A Function to transform the results of the provided future to the results of
   *     the returned future.

   * iterable. The key used to store that value in the multimap will be the result of calling the
   * function on that value. The resulting multimap is created as an immutable snapshot. In the
   * returned multimap, keys appear in the order they are first encountered, and the values
   * corresponding to each key appear in the same order as they are encountered.
   *