public static <
          T extends @Nullable Object,
          K extends @Nullable Object,
          V extends @Nullable Object,
          M extends Multimap<K, V>>
      Collector<T, ?, M> flatteningToMultimap(
          java.util.function.Function<? super T, ? extends K> keyFunction,
          java.util.function.Function<? super T, ? extends Stream<? extends V>> valueFunction,

    }

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

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

    }

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

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

    }

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

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

    }

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

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

    }

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

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

    List<?> getWildcardProp() { return null; }

    List<? extends CombinedInterface> getUpperBoundProp() { return null; }

    List<? super CombinedInterface> getLowerBoundProp() { return null; }

    List<? super Set<? extends Map<?, CombinedInterface[]>>>[] getNestedProp() { return null; }

    <T extends JavaInterface> T paramMethod(T param) {
        return null;
    }

  public static final class TwoArgConstructorException extends Exception {
    public TwoArgConstructorException(String message, Throwable cause) {
      super(message, cause);
    }
  }

  public static final class TwoArgConstructorRuntimeException extends RuntimeException {
    public TwoArgConstructorRuntimeException(String message, Throwable cause) {
      super(message, cause);

  }

  public static <E extends Comparable<? super E>> ImmutableSortedSet<E> of(E e1) {
    return ofInternal(Ordering.natural(), e1);
  }

  @SuppressWarnings("unchecked")
  public static <E extends Comparable<? super E>> ImmutableSortedSet<E> of(E e1, E e2) {
    return ofInternal(Ordering.natural(), e1, e2);
  }

  @SuppressWarnings("unchecked")

     * operation O(1).
     */

    private @Nullable Iterator<? extends Iterator<? extends T>> topMetaIterator;

    // Only becomes nonnull if we encounter nested concatenations.
    private @Nullable Deque<Iterator<? extends Iterator<? extends T>>> metaIterators;

    ConcatenatedIterator(Iterator<? extends Iterator<? extends T>> metaIterator) {
      iterator = emptyIterator();