return delegate().edgeValue(endpoints);
  }

  @Override
  public @Nullable V edgeValueOrDefault(N nodeU, N nodeV, @Nullable V defaultValue) {
    return delegate().edgeValueOrDefault(nodeU, nodeV, defaultValue);
  }

  @Override
  public @Nullable V edgeValueOrDefault(EndpointPair<N> endpoints, @Nullable V defaultValue) {
    return delegate().edgeValueOrDefault(endpoints, defaultValue);
  }

   * entries {@code [0, 1) => 3, [1, 2] => 3, (2, 5] => 3}.
   *
   * @since 28.1
   */
  void merge(
      Range<K> range,
      @Nullable V value,
      BiFunction<? super V, ? super @Nullable V, ? extends @Nullable V> remappingFunction);

  /**
   * Returns a view of this range map as an unmodifiable {@code Map<Range<K>, V>}. Modifications to

  @Override
  ContiguousSet<C> tailSetImpl(C fromElement, boolean fromInclusive) {
    return this;
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return false;
  }

  @GwtIncompatible // not used by GWT emulation
  @Override
  int indexOf(@Nullable Object target) {
    return -1;
  }

  @Override
  public UnmodifiableIterator<C> iterator() {
    return emptyIterator();
  }

    LAST_BEFORE {
      @Override
      public <E extends @Nullable Object> int resultIndex(
          Comparator<? super E> comparator,
          @ParametricNullness E key,
          List<? extends E> list,
          int foundIndex) {
        return FIRST_PRESENT.resultIndex(comparator, key, list, foundIndex) - 1;
      }
    };

    abstract <E extends @Nullable Object> int resultIndex(
        Comparator<? super E> comparator,

   */
  // All subclasses are owned by us and we'll make sure to get the R type right, including nullness.
  @SuppressWarnings({"unchecked", "nullness"})
  @CanIgnoreReturnValue
  public final @Nullable R invoke(@Nullable T receiver, @Nullable Object... args)
      throws InvocationTargetException, IllegalAccessException {
    return (R) invokeInternal(receiver, checkNotNull(args));
  }

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

/**
 * An iterator that transforms a backing iterator; for internal use. This avoids the object overhead
 * of constructing a {@link com.google.common.base.Function Function} for internal methods.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
abstract class TransformedIterator<F extends @Nullable Object, T extends @Nullable Object>
    implements Iterator<T> {

    private static final AtomicReferenceFieldUpdater<Waiter, @Nullable Thread> waiterThreadUpdater =
        AtomicReferenceFieldUpdater.<Waiter, @Nullable Thread>newUpdater(
            Waiter.class, Thread.class, "thread");
    private static final AtomicReferenceFieldUpdater<Waiter, @Nullable Waiter> waiterNextUpdater =
        AtomicReferenceFieldUpdater.<Waiter, @Nullable Waiter>newUpdater(
            Waiter.class, Waiter.class, "next");

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

@GwtCompatible
@NullMarked
public class Helpers {
  // Clone of Objects.equals
  static boolean equal(@Nullable Object a, @Nullable Object b) {
    return a == b || (a != null && a.equals(b));
  }

  // Clone of Lists.newArrayList
  public static <E extends @Nullable Object> List<E> copyToList(Iterable<? extends E> elements) {

    }
  }

  private static <V> ImmutableSet<V> valueSet(
      @Nullable Comparator<? super V> valueComparator, Collection<? extends V> values) {
    return (valueComparator == null)
        ? ImmutableSet.copyOf(values)
        : ImmutableSortedSet.copyOf(valueComparator, values);
  }

  private static <V> ImmutableSet<V> emptySet(@Nullable Comparator<? super V> valueComparator) {
    return (valueComparator == null)

   */
  @Override
  public boolean containsValue(@Nullable Object value) {
    return findEntryByValue(value) != ABSENT;
  }

  @Override
  public @Nullable V get(@Nullable Object key) {
    int entry = findEntryByKey(key);
    return (entry == ABSENT) ? null : values[entry];
  }

  @Nullable K getInverse(@Nullable Object value) {
    int entry = findEntryByValue(value);