this.forward = forward;
  }

  @Override
  public int count(@Nullable Object element) {
    return forward.count(element);
  }

  @Override
  public @Nullable Entry<E> firstEntry() {
    return forward.lastEntry();
  }

  @Override
  public @Nullable Entry<E> lastEntry() {
    return forward.firstEntry();
  }

  @Override
  public int size() {

 * invoke methods, they invoke methods on the {@code ForwardingSetMultimap}.
 *
 * @author Kurt Alfred Kluever
 * @since 3.0
 */
@GwtCompatible
public abstract class ForwardingSetMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends ForwardingMultimap<K, V> implements SetMultimap<K, V> {
  /** Constructor for use by subclasses. */
  public ForwardingSetMultimap() {}

  @Override

import java.util.Map;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates maps, containing sample elements, to be tested.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@NullMarked
public interface TestMapGenerator<K extends @Nullable Object, V extends @Nullable Object>
    extends TestContainerGenerator<Map<K, V>, Map.Entry<K, V>> {
  K[] createKeyArray(int length);

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nullable;

/**
 * A dependency exclusion.
 *
 * @since 4.0.0
 * @see DependencyCoordinates#getExclusions()
 */
@Experimental
public interface Exclusion {
    @Nullable
    String getGroupId();

    @Nullable
    String getArtifactId();

 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multimap">{@code Multimap}</a>.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class ArrayListMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractListMultimap<K, V> {
  // Default from ArrayList
  private static final int DEFAULT_VALUES_PER_KEY = 3;

  @VisibleForTesting transient int expectedValuesPerKey;

  /**

    final Alphabet alphabet;

    final @Nullable Character paddingChar;

    StandardBaseEncoding(String name, String alphabetChars, @Nullable Character paddingChar) {
      this(new Alphabet(name, alphabetChars.toCharArray()), paddingChar);
    }

    StandardBaseEncoding(Alphabet alphabet, @Nullable Character paddingChar) {
      this.alphabet = checkNotNull(alphabet);
      checkArgument(

import java.util.SortedMap;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sorted maps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestSortedMapGenerator<K extends @Nullable Object, V extends @Nullable Object>
    extends TestMapGenerator<K, V> {
  @Override
  SortedMap<K, V> create(Object... elements);

   *
   * <p>For more background, see {@code ConcurrentHashMultiset.deserializationReplacement}.
   */
  private transient @Nullable ImmutableSetMultimap<?, ?> deserializationReplacement;

  ImmutableSetMultimap(
      ImmutableMap<K, ImmutableSet<V>> map,
      int size,
      @Nullable Comparator<? super V> valueComparator) {
    super(map, size);
    this.emptySet = emptySet(valueComparator);
  }

  // views

    return super.toString();
  }

  @Override
  public boolean equals(@Nullable Object o) {
    assertTrue(Thread.holdsLock(mutex));
    return super.equals(o);
  }

  @Override
  public int hashCode() {
    assertTrue(Thread.holdsLock(mutex));
    return super.hashCode();
  }

  @Override
  public boolean add(@Nullable E o) {
    assertTrue(Thread.holdsLock(mutex));
    return super.add(o);
  }

  @SuppressWarnings("NullableOptional") // Null passthrough is reasonable for type conversions
  @IgnoreJRERequirement // Users will use this only if they're already using Optional.
  public static <T> @Nullable Optional<T> fromJavaUtil(
      java.util.@Nullable Optional<T> javaUtilOptional) {
    return (javaUtilOptional == null) ? null : fromNullable(javaUtilOptional.orElse(null));
  }

  /**