UncheckedThrowingFuture<V> future = new UncheckedThrowingFuture<V>();
    future.complete(checkNotNull(error));
    return future;
  }

  public static <V> ListenableFuture<V> throwingRuntimeException(RuntimeException e) {
    UncheckedThrowingFuture<V> future = new UncheckedThrowingFuture<V>();
    future.complete(checkNotNull(e));
    return future;
  }

  public static <V> UncheckedThrowingFuture<V> incomplete() {

      String relationshipName,
      String hashName,
      ItemReporter itemReporter) {
    this.equivalence = checkNotNull(equivalence);
    this.relationshipName = checkNotNull(relationshipName);
    this.hashName = checkNotNull(hashName);
    this.itemReporter = checkNotNull(itemReporter);
  }

  // TODO(cpovirk): should we reject null items, since the tests already check null automatically?
  @CanIgnoreReturnValue

  private final int bits;
  private final boolean supportsClone;

  MacHashFunction(String algorithmName, Key key, String toString) {
    this.prototype = getMac(algorithmName, key);
    this.key = checkNotNull(key);
    this.toString = checkNotNull(toString);
    this.bits = prototype.getMacLength() * Byte.SIZE;
    this.supportsClone = supportsClone(prototype);
  }

  @Override
  public int bits() {
    return bits;
  }

  }

  @Override
  public boolean hasEdgeConnecting(N nodeU, N nodeV) {
    return hasEdgeConnectingInternal(checkNotNull(nodeU), checkNotNull(nodeV));
  }

  @Override
  public boolean hasEdgeConnecting(EndpointPair<N> endpoints) {
    checkNotNull(endpoints);
    return isOrderingCompatible(endpoints)
        && hasEdgeConnectingInternal(endpoints.nodeU(), endpoints.nodeV());
  }

   */
  SubscriberExceptionContext(
      EventBus eventBus, Object event, Object subscriber, Method subscriberMethod) {
    this.eventBus = checkNotNull(eventBus);
    this.event = checkNotNull(event);
    this.subscriber = checkNotNull(subscriber);
    this.subscriberMethod = checkNotNull(subscriberMethod);
  }

  /**
   * Returns the {@link EventBus} that handled the event and the subscriber. Useful for broadcasting

  static <E> InvalidatableSet<E> of(
      Set<E> delegate, Supplier<Boolean> validator, Supplier<String> errorMessage) {
    return new InvalidatableSet<>(
        checkNotNull(delegate), checkNotNull(validator), checkNotNull(errorMessage));
  }

  @Override
  protected Set<E> delegate() {
    validate();
    return delegate;
  }

  private InvalidatableSet(

    this.singleRowKey = checkNotNull(rowKey);
    this.singleColumnKey = checkNotNull(columnKey);
    this.singleValue = checkNotNull(value);
  }

  SingletonImmutableTable(Cell<R, C, V> cell) {
    this(cell.getRowKey(), cell.getColumnKey(), cell.getValue());
  }

  @Override
  public ImmutableMap<R, V> column(C columnKey) {
    checkNotNull(columnKey);
    return containsColumn(columnKey)

  }

  @Override
  public T or(T defaultValue) {
    checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
    return reference;
  }

  @Override
  public Optional<T> or(Optional<? extends T> secondChoice) {
    checkNotNull(secondChoice);
    return this;
  }

  @Override
  public T or(Supplier<? extends T> supplier) {
    checkNotNull(supplier);
    return reference;
  }

  @Override

  public void testCheckNotNull_simple_success() {
    String result = checkNotNull(NON_NULL_STRING);
    assertSame(NON_NULL_STRING, result);
  }

  public void testCheckNotNull_simple_failure() {
    assertThrows(NullPointerException.class, () -> checkNotNull(null));
  }

  public void testCheckNotNull_simpleMessage_success() {
    String result = checkNotNull(NON_NULL_STRING, IGNORE_ME);
    assertSame(NON_NULL_STRING, result);

      return result;
    }
    return new UnmodifiableMultiset<>(checkNotNull(multiset));
  }

  /**
   * Simply returns its argument.
   *
   * @deprecated no need to use this
   * @since 10.0
   */
  @InlineMe(
      replacement = "checkNotNull(multiset)",
      staticImports = "com.google.common.base.Preconditions.checkNotNull")
  @Deprecated