import java.util.function.Consumer;
import org.checkerframework.checker.nullness.qual.Nullable;

@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
abstract class IndexedImmutableSet<E> extends ImmutableSet.CachingAsList<E> {
  abstract E get(int index);

  @Override
  public UnmodifiableIterator<E> iterator() {
    return asList().iterator();
  }

  @Override
  public Spliterator<E> spliterator() {

 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault
final class RegularImmutableSet<E> extends ImmutableSet.CachingAsList<E> {
  private static final Object[] EMPTY_ARRAY = new Object[0];
  static final RegularImmutableSet<Object> EMPTY =
      new RegularImmutableSet<>(EMPTY_ARRAY, 0, EMPTY_ARRAY, 0);

 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
abstract class ImmutableMapEntrySet<K, V> extends ImmutableSet.CachingAsList<Entry<K, V>> {
  static final class RegularEntrySet<K, V> extends ImmutableMapEntrySet<K, V> {
    private final transient ImmutableMap<K, V> map;
    private final transient ImmutableList<Entry<K, V>> entries;

@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // we're overriding default serialization
@ElementTypesAreNonnullByDefault
public abstract class ImmutableSortedSet<E> extends ImmutableSet.CachingAsList<E>
    implements NavigableSet<E>, SortedIterable<E> {
  static final int SPLITERATOR_CHARACTERISTICS =
      ImmutableSet.SPLITERATOR_CHARACTERISTICS | Spliterator.SORTED;

  /**