import org.jspecify.annotations.Nullable;

/**
 * This class provides a skeletal implementation of the {@link ListIterator} interface across a
 * fixed number of elements that may be retrieved by position. It does not support {@link #remove},
 * {@link #set}, or {@link #add}.
 *
 * @author Jared Levy
 */
@GwtCompatible
abstract class AbstractIndexedListIterator<E extends @Nullable Object>
    extends UnmodifiableListIterator<E> {

import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(SetMultimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class FilteredKeySetMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends FilteredKeyMultimap<K, V> implements FilteredSetMultimap<K, V> {

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multisets, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public interface TestMultisetGenerator<E extends @Nullable Object>
    extends TestCollectionGenerator<E> {
  @Override
  Multiset<E> create(Object... elements);

  @Override
  public Comparator<? super K> comparator() {
    return comparator;
  }

  @Override
  public @Nullable K firstKey() {
    return sortedDelegate.firstKey();
  }

  @Override
  public @Nullable K lastKey() {
    return sortedDelegate.lastKey();
  }

  @Nullable K higher(K k) {
    Iterator<K> iterator = keySet().tailSet(k).iterator();
    while (iterator.hasNext()) {

 * @since 9.0 (in 1.0 as {@code ValueFuture})
 */
@GwtCompatible
public final class SettableFuture<V extends @Nullable Object>
    extends AbstractFuture.TrustedFuture<V> {
  /**
   * Creates a new {@code SettableFuture} that can be completed or cancelled by a later method call.
   */
  public static <V extends @Nullable Object> SettableFuture<V> create() {
    return new SettableFuture<>();
  }

  @CanIgnoreReturnValue
  @Override

     */
    @Nullable
    VersionRange getVersionRange();

    /**
     * Returns the recommended version of this constraint, or {@code null} if none.
     * <p>
     * Note: only one, this method or {@link #getVersionRange()} method must return non-{@code null} value.
     */
    @Nullable
    Version getRecommendedVersion();

    /**

@GwtCompatible
public abstract class FluentFuture<V extends @Nullable Object>
    extends GwtFluentFutureCatchingSpecialization<V> {

  /**
   * A less abstract subclass of AbstractFuture. This can be used to optimize setFuture by ensuring
   * that {@link #get} calls exactly the implementation of {@link AbstractFuture#get}.
   */
  abstract static class TrustedFuture<V extends @Nullable Object> extends FluentFuture<V>

    checkNotNull(valueComparator);
    return Comparator.<Optional<T>, @Nullable T>comparing(
        o -> orElseNull(o), Comparator.nullsLast(valueComparator));
  }

  // For discussion of why this exists, see the Android flavor.
  private static <T> @Nullable T orElseNull(Optional<T> optional) {
    return optional.orElse(null);
  }

  /**

  @Override
  public E takeLast() throws InterruptedException {
    return delegate().takeLast();
  }

  @Override
  public @Nullable E pollFirst(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().pollFirst(timeout, unit);
  }

  @Override
  public @Nullable E pollLast(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().pollLast(timeout, unit);
  }

  @Override

  }

  public void testNullFriendlyTransform() {
    List<@Nullable Integer> input = asList(1, 2, null, 3);
    Iterable<String> result =
        Iterables.transform(
            input,
            new Function<@Nullable Integer, String>() {
              @Override
              public String apply(@Nullable Integer from) {
                return String.valueOf(from);
              }
            });