// requireNonNull is safe because of the hasNext check.
      BiEntry<K, V> entry = requireNonNull(next);
      next = entry.nextInKeyInsertionOrder;
      toRemove = entry;
      remaining--;
      return output(entry);
    }

    @Override
    public void remove() {
      if (modCount != expectedModCount) {
        throw new ConcurrentModificationException();
      }
      if (toRemove == null) {

      AsyncFunction<? super I, ? extends O> function,
      Executor executor) {
    checkNotNull(executor);
    AsyncTransformFuture<I, O> output = new AsyncTransformFuture<>(input, function);
    input.addListener(output, rejectionPropagatingExecutor(executor, output));
    return output;
  }

  static <I extends @Nullable Object, O extends @Nullable Object> ListenableFuture<O> create(

   * Multimap} entries in two distinct modes:
   *
   * <ul>
   *   <li>To output a separate entry for each key-value pair, pass {@code multimap.entries()} to a
   *       {@code MapJoiner} method that accepts entries as input, and receive output of the form
   *       {@code key1=A&key1=B&key2=C}.
   *   <li>To output a single entry for each key, pass {@code multimap.asMap()} to a {@code

     * Adds a name/value pair to the formatted output in {@code name=value} format.
     *
     * @since 18.0 (since 11.0 as {@code Objects.ToStringHelper.add()}).
     */
    @CanIgnoreReturnValue
    public ToStringHelper add(String name, boolean value) {
      return addUnconditionalHolder(name, String.valueOf(value));
    }

    /**
     * Adds a name/value pair to the formatted output in {@code name=value} format.
     *

   * primary input succeeds, it is never invoked. If, during the invocation of {@code fallback}, an
   * exception is thrown, this exception is used as the result of the output {@code Future}.
   *
   * <p>Usage example:
   *
   * <pre>{@code
   * // Falling back to a zero counter in case an exception happens when processing the RPC to fetch
   * // counters.

    final DataOutput output;
    final ByteArrayOutputStream byteArrayOutputStream;

    ByteArrayDataOutputStream(ByteArrayOutputStream byteArrayOutputStream) {
      this.byteArrayOutputStream = byteArrayOutputStream;
      output = new DataOutputStream(byteArrayOutputStream);
    }

    @Override
    public void write(int b) {
      try {
        output.write(b);

 *
 * @param <InputT> the type of the individual inputs
 * @param <OutputT> the type of the output (i.e. this) future
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
abstract class AggregateFuture<InputT extends @Nullable Object, OutputT extends @Nullable Object>
    extends AggregateFutureState<OutputT> {
  private static final LazyLogger logger = new LazyLogger(AggregateFuture.class);

  /**

    return newReentrantLock(lockName, false);
  }

  /**
   * Creates a {@link ReentrantLock} with the given fairness policy. The {@code lockName} is used in
   * the warning or exception output to help identify the locks involved in the detected deadlock.
   */
  public ReentrantLock newReentrantLock(String lockName, boolean fair) {
    return policy == Policies.DISABLED
        ? new ReentrantLock(fair)

    if (collection == null) {
      return createUnmodifiableEmptyCollection();
    }

    Collection<V> output = createCollection();
    output.addAll(collection);
    totalSize -= collection.size();
    collection.clear();

    return unmodifiableCollectionSubclass(output);
  }

  <E extends @Nullable Object> Collection<E> unmodifiableCollectionSubclass(
      Collection<E> collection) {

   * {@code output}.
   *
   * @return the number of bytes copied
   * @throws IOException if an I/O error occurs while reading from this source or writing to {@code
   *     output}
   */
  @CanIgnoreReturnValue
  public long copyTo(OutputStream output) throws IOException {
    checkNotNull(output);

    Closer closer = Closer.create();
    try {