concatenated.close();
    assertThat(closeCountB.get()).isEqualTo(1);
  }

  public void testConcat_refStream_closeIsPropagated_Stream_flatMap() {
    // Just to demonstrate behavior of Stream::flatMap in the standard library
    AtomicInteger closeCountB = new AtomicInteger(0);
    Stream<String> streamB = Stream.of("b").onClose(closeCountB::incrementAndGet);
    Stream<String> concatenated =

      Spliterator<OutElementT> flatMap(
          Spliterator<InElementT> fromSpliterator,
          Function<? super InElementT, @Nullable Spliterator<OutElementT>> function,
          int topCharacteristics,
          long topSize) {
    checkArgument(
        (topCharacteristics & Spliterator.SUBSIZED) == 0,
        "flatMap does not support SUBSIZED characteristic");
    checkArgument(

@GwtIncompatible
public class ImmutableBiMapFloodingTest extends AbstractHashFloodingTest<BiMap<Object, Object>> {
  public ImmutableBiMapFloodingTest() {
    super(
        EnumSet.allOf(ConstructionPathway.class).stream()
            .flatMap(
                path ->
                    Stream.<Construction<BiMap<Object, Object>>>of(
                        keys ->
                            path.create(
                                Lists.transform(

 * relevant methods below.
 *
 * <ul>
 *   <li>This class is serializable; {@code java.util.Optional} is not.
 *   <li>{@code java.util.Optional} has the additional methods {@code ifPresent}, {@code filter},
 *       {@code flatMap}, and {@code orElseThrow}.
 *   <li>{@code java.util} offers the primitive-specialized versions {@code OptionalInt}, {@code
 *       OptionalLong} and {@code OptionalDouble}, the use of which is recommended; Guava does not

   * iterator supports it.
   *
   * <p><b>{@code Stream} equivalent:</b> to concatenate an arbitrary number of streams, use {@code
   * Stream.of(stream1, stream2, ...).flatMap(s -> s)}. If the sources are iterables, use {@code
   * Stream.of(iter1, iter2, ...).flatMap(Streams::stream)}.
   *
   * @throws NullPointerException if any of the provided iterables is {@code null}
   * @since 20.0
   */
  @SafeVarargs

   * Iterables.concat(Collections.nCopies(n, iterable))}
   *
   * <p><b>Java 8+ users:</b> The {@code Stream} equivalent of this method is {@code
   * Stream.generate(() -> iterable).flatMap(Streams::stream)}.
   */
  public static <T extends @Nullable Object> Iterable<T> cycle(final Iterable<T> iterable) {
    checkNotNull(iterable);
    return new FluentIterable<T>() {
      @Override

 * relevant methods below.
 *
 * <ul>
 *   <li>This class is serializable; {@code java.util.Optional} is not.
 *   <li>{@code java.util.Optional} has the additional methods {@code ifPresent}, {@code filter},
 *       {@code flatMap}, and {@code orElseThrow}.
 *   <li>{@code java.util} offers the primitive-specialized versions {@code OptionalInt}, {@code
 *       OptionalLong} and {@code OptionalDouble}, the use of which is recommended; Guava does not

   * Iterables.concat(Collections.nCopies(n, iterable))}
   *
   * <p><b>Java 8+ users:</b> The {@code Stream} equivalent of this method is {@code
   * Stream.generate(() -> iterable).flatMap(Streams::stream)}.
   */
  public static <T extends @Nullable Object> Iterable<T> cycle(final Iterable<T> iterable) {
    checkNotNull(iterable);
    return new FluentIterable<T>() {
      @Override

        .expect("A", "B", "C", "D", "E");
  }

  public void testFlatMap() {
    SpliteratorTester.of(
            () ->
                CollectSpliterators.flatMap(
                    Arrays.spliterator(new String[] {"abc", "", "de", "f", "g", ""}),
                    (String str) -> Lists.charactersOf(str).spliterator(),

         */
        return immutableEntry(requireNonNull(currentKey), valueItr.next());
      }
    };
  }

  @Override
  Spliterator<Entry<K, V>> entrySpliterator() {
    return CollectSpliterators.flatMap(
        asMap().entrySet().spliterator(),
        keyToValueCollectionEntry -> {
          K key = keyToValueCollectionEntry.getKey();
          Collection<V> valueCollection = keyToValueCollectionEntry.getValue();