import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of a {@link SortedSetMultimap} with a sorted key set.
 *
 * <p>This superclass allows {@code TreeMultimap} to override methods to return navigable set and
 * map types in non-GWT only, while GWT code will inherit the SortedMap/SortedSet overrides.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

    implements TestSortedSetGenerator<String> {

  @Override
  public SortedSet<String> create(Object... elements) {
    return (SortedSet<String>) super.create(elements);
  }

  @Override
  protected abstract SortedSet<String> create(String[] elements);

  /** Sorts the elements by their natural ordering. */
  /*

  public void testEmpty_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    SortedSet<String> copy = SerializableTester.reserializeAndAssert(set);
    assertEquals(set.comparator(), copy.comparator());
  }

  @GwtIncompatible // SerializableTester
  public void testSingle_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    set.add("e");

import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of a {@link SortedSetMultimap} with a sorted key set.
 *
 * <p>This superclass allows {@code TreeMultimap} to override methods to return navigable set and
 * map types in non-GWT only, while GWT code will inherit the SortedMap/SortedSet overrides.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

    implements TestSortedSetGenerator<String> {

  @Override
  public SortedSet<String> create(Object... elements) {
    return (SortedSet<String>) super.create(elements);
  }

  @Override
  protected abstract SortedSet<String> create(String[] elements);

  /** Sorts the elements by their natural ordering. */
  /*

  @Override
  protected abstract SortedSetMultimap<K, V> delegate();

  @Override
  public SortedSet<V> get(@ParametricNullness K key) {
    return delegate().get(key);
  }

  @Override
  public SortedSet<V> removeAll(@Nullable Object key) {
    return delegate().removeAll(key);
  }

  @Override
  public SortedSet<V> replaceValues(@ParametricNullness K key, Iterable<? extends V> values) {

    Comparator<?> comparator2;
    if (elements instanceof SortedSet) {
      comparator2 = comparator((SortedSet<?>) elements);
    } else if (elements instanceof SortedIterable) {
      comparator2 = ((SortedIterable<?>) elements).comparator();
    } else {
      return false;
    }
    return comparator.equals(comparator2);
  }

  @SuppressWarnings("unchecked")
  // if sortedSet.comparator() is null, the set must be naturally ordered

      return multiset().comparator();
    }

    @Override
    public SortedSet<E> subSet(@ParametricNullness E fromElement, @ParametricNullness E toElement) {
      return multiset().subMultiset(fromElement, CLOSED, toElement, OPEN).elementSet();
    }

    @Override
    public SortedSet<E> headSet(@ParametricNullness E toElement) {
      return multiset().headMultiset(toElement, OPEN).elementSet();
    }

  @Override
  public Comparator<? super E> comparator() {
    return delegate().comparator();
  }

  @Override
  SortedSet<E> createElementSet() {
    return Collections.unmodifiableSortedSet(delegate().elementSet());
  }

  @Override
  public SortedSet<E> elementSet() {
    return (SortedSet<E>) super.elementSet();
  }

  private transient @Nullable UnmodifiableSortedMultiset<E> descendingMultiset;

  @Override

  }

  private static <E extends @Nullable Object> SortedSet<E> sortedSet(
      SortedSet<E> set, @Nullable Object mutex) {
    return new SynchronizedSortedSet<>(set, mutex);
  }

  static class SynchronizedSortedSet<E extends @Nullable Object> extends SynchronizedSet<E>
      implements SortedSet<E> {
    SynchronizedSortedSet(SortedSet<E> delegate, @Nullable Object mutex) {
      super(delegate, mutex);
    }