public @Nullable E higher(@ParametricNullness E e) {
      return delegate.higher(e);
    }

    @Override
    public @Nullable E pollFirst() {
      throw new UnsupportedOperationException();
    }

    @Override
    public @Nullable E pollLast() {
      throw new UnsupportedOperationException();
    }

    @LazyInit private transient @Nullable UnmodifiableNavigableSet<E> descendingSet;

    READY,
    NOT_READY,
    DONE,
    FAILED,
  }

  private @Nullable T next;

  protected abstract @Nullable T computeNext();

  @CanIgnoreReturnValue
  protected final @Nullable T endOfData() {
    state = State.DONE;
    return null;
  }

  @Override
  public final boolean hasNext() {
    checkState(state != State.FAILED);
    switch (state) {
      case DONE:
        return false;

     * Check if the personality is "maven3".
     */
    public static boolean mavenMaven3Personality(@Nullable Map<String, ?> userProperties) {
        return doGet(userProperties, Constants.MAVEN_MAVEN3_PERSONALITY, false);
    }

    /**
     * Check if the consumer POM feature is active.
     */
    public static boolean consumerPom(@Nullable Map<String, ?> userProperties) {

 * way that affects its {@link Object#equals} behavior. Undefined behavior and bugs will result.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class HashMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractSetMultimap<K, V> {
  private static final int DEFAULT_VALUES_PER_KEY = 2;

  @VisibleForTesting transient int expectedValuesPerKey = DEFAULT_VALUES_PER_KEY;

  /**

    return size() == 0;
  }

  @Override
  public boolean containsKey(@Nullable Object key) {
    return get(key) != null;
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return values().contains(value);
  }

  // Overriding to mark it Nullable
  @Override
  public abstract @Nullable V get(@Nullable Object key);

  /**

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import java.util.Comparator;
import org.jspecify.annotations.Nullable;

/** An ordering for a pre-existing comparator. */
@GwtCompatible
final class ComparatorOrdering<T extends @Nullable Object> extends Ordering<T>
    implements Serializable {
  final Comparator<T> comparator;

  ComparatorOrdering(Comparator<T> comparator) {

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import java.util.Collection;
import org.jspecify.annotations.Nullable;

/**
 * A GWT-only class only used by GWT emulations. It is used to consolidate the definitions of method
 * delegation to save code size.
 *
 * @author Hayward Chan
 */

import org.jspecify.annotations.Nullable;

/**
 * Tests for {@link AbstractFuture} that use a non-{@link TrustedFuture} for {@link
 * AbstractFuture#setFuture} calls.
 */
@GwtCompatible
@NullUnmarked
public class UntrustedInputFutureTest extends AbstractAbstractFutureTest {
  @Override
  AbstractFuture<@Nullable Integer> newDelegate() {

 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multimap">{@code Multimap}</a>.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public interface SetMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends Multimap<K, V> {
  /**
   * {@inheritDoc}
   *
   * <p>Because a {@code SetMultimap} has unique values for a given key, this method returns a

 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#bimap">{@code BiMap}</a>.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
public interface BiMap<K extends @Nullable Object, V extends @Nullable Object> extends Map<K, V> {
  // Modification Operations

  /**
   * {@inheritDoc}
   *
   * @throws IllegalArgumentException if the given value is already bound to a different key in this