}

    protected <ENTITY extends ElevateWordToLabel> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected ElevateWordToLabelCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends KeyMatch> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected KeyMatchCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends RelatedContent> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected RelatedContentCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends RelatedQuery> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected RelatedQueryCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends FavoriteLog> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected FavoriteLogCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

    }

    protected <ENTITY extends Group> ENTITY doSelectByPK(String id, Class<? extends ENTITY> tp) {
        return doSelectEntity(xprepareCBAsPK(id), tp);
    }

    protected GroupCB xprepareCBAsPK(String id) {
        assertObjectNotNull("id", id);
        return newConditionBean().acceptPK(id);
    }

   *
   * @since 3.0
   */
  public static <E extends @Nullable Object> SetView<E> symmetricDifference(
      Set<? extends E> set1, Set<? extends E> set2) {
    checkNotNull(set1, "set1");
    checkNotNull(set2, "set2");

    return new SetView<E>() {
      @Override
      public UnmodifiableIterator<E> iterator() {
        Iterator<? extends E> itr1 = set1.iterator();

  @SuppressWarnings("unchecked")
  private static <T extends @Nullable Object> ListenableFuture<? extends T>[] gwtCompatibleToArray(
      Iterable<? extends ListenableFuture<? extends T>> futures) {
    Collection<ListenableFuture<? extends T>> collection;
    if (futures instanceof Collection) {
      collection = (Collection<ListenableFuture<? extends T>>) futures;
    } else {
      collection = ImmutableList.copyOf(futures);

   */
  @GwtIncompatible // Array.newInstance(Class, int)
  public static <T extends @Nullable Object> T[] toArray(
      Iterable<? extends T> iterable, Class<@NonNull T> type) {
    return toArray(iterable, ObjectArrays.newArray(type, 0));
  }

  static <T extends @Nullable Object> T[] toArray(Iterable<? extends T> iterable, T[] array) {
    Collection<? extends T> collection = castOrCopyToCollection(iterable);

 * @since 13.0
 */
public final class MutableTypeToInstanceMap<B extends @Nullable Object>
    extends ForwardingMap<TypeToken<? extends @NonNull B>, B> implements TypeToInstanceMap<B> {
  /** Creates a new map. */
  public MutableTypeToInstanceMap() {}

  private final Map<TypeToken<? extends @NonNull B>, B> backingMap = new HashMap<>();

  @Override
  public <T extends @NonNull B> @Nullable T getInstance(Class<T> type) {