}

  public void testToOptionalSingleton() {
    assertThat(Stream.of(1).collect(toOptional())).hasValue(1);
  }

  public void testToOptionalNull() {
    Stream<@Nullable Object> stream = Stream.of((Object) null);
    assertThrows(NullPointerException.class, () -> stream.collect(toOptional()));
  }

  public void testToOptionalMultiple() {
    IllegalArgumentException expected =

    delegateList.forEach(action);
  }

  @GwtIncompatible // not present in emulated superclass
  @Override
  int copyIntoArray(@Nullable Object[] dst, int offset) {
    return delegateList.copyIntoArray(dst, offset);
  }

  @Override
  @CheckForNull
  Object[] internalArray() {
    return delegateList.internalArray();
  }

  @Override
  int internalArrayStart() {
    return delegateList.internalArrayStart();

 *
 * @author Chris Povirk
 */
final class Platform {
  /** Serializes and deserializes the specified object (a no-op under GWT). */
  @SuppressWarnings("unchecked")
  static <T> T reserialize(T object) {
    return checkNotNull(object);
  }

  private Platform() {}

      this.gen = gen;
    }

    @Override
    public SampleElements<E> samples() {
      return gen.samples();
    }

    @Override
    public Set<E> create(Object... elements) {
      Object[] duplicated = new Object[elements.length * 2];
      for (int i = 0; i < elements.length; i++) {
        duplicated[i] = elements[i];
        duplicated[i + elements.length] = elements[i];
      }

  public Iterator<E> iterator() {
    return Multisets.iteratorImpl(this);
  }

  @Override
  public @Nullable Object[] toArray() {
    return standardToArray();
  }

  @Override
  @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
  public <T extends @Nullable Object> T[] toArray(T[] array) {
    return standardToArray(array);
  }

  @Override
  public String toString() {

    @Override
    public V getValue() {
      return value;
    }

    @Override
    public boolean equals(@CheckForNull Object object) {
      // Cannot use key and value equivalence
      if (object instanceof Entry) {
        Entry<?, ?> that = (Entry<?, ?>) object;
        return key.equals(that.getKey()) && value.equals(that.getValue());
      }
      return false;
    }

    @Override

  "nullness", // TODO(b/147136275): Remove once our checker understands & and |.
})
abstract class AbstractCatchingFuture<
        V extends @Nullable Object, X extends Throwable, F, T extends @Nullable Object>
    extends FluentFuture.TrustedFuture<V> implements Runnable {
  static <V extends @Nullable Object, X extends Throwable> ListenableFuture<V> create(
      ListenableFuture<? extends V> input,
      Class<X> exceptionType,

    testComparator(NullsBeforeB.INSTANCE, "a", "azzzzzz", null, "b", "c");
  }

  public void testIsEmpty_iterable() {
    List<Object> list = new ArrayList<>();
    assertEmpty(list);
    assertEmpty(
        new Iterable<Object>() {
          @Override
          public Iterator<Object> iterator() {
            return emptyList().iterator();
          }
        });

    list.add("a");
    try {

    testComparator(NullsBeforeB.INSTANCE, "a", "azzzzzz", null, "b", "c");
  }

  public void testIsEmpty_iterable() {
    List<Object> list = new ArrayList<>();
    assertEmpty(list);
    assertEmpty(
        new Iterable<Object>() {
          @Override
          public Iterator<Object> iterator() {
            return emptyList().iterator();
          }
        });

    list.add("a");
    try {

    public Ints() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super(1, 0, 2, 3, 4);
    }
  }

  public static <K extends @Nullable Object, V extends @Nullable Object>
      SampleElements<Entry<K, V>> mapEntries(SampleElements<K> keys, SampleElements<V> values) {
    return new SampleElements<>(
        mapEntry(keys.e0(), values.e0()),
        mapEntry(keys.e1(), values.e1()),