/**
   * Returns the comparator that orders the multimap values, with {@code null} indicating that
   * natural ordering is used.
   */
  @CheckForNull
  Comparator<? super V> valueComparator();

    transient Supplier<? extends SortedSet<V>> factory;
    @CheckForNull transient Comparator<? super V> valueComparator;

    CustomSortedSetMultimap(Map<K, Collection<V>> map, Supplier<? extends SortedSet<V>> factory) {
      super(map);
      this.factory = checkNotNull(factory);
      valueComparator = factory.get().comparator();
    }

    @Override
    Set<K> createKeySet() {

    Builder<K, V> combine(Builder<K, V> other) {
      super.combine(other);
      return this;
    }

    @Override
    public Builder<K, V> orderEntriesByValue(Comparator<? super V> valueComparator) {
      throw new UnsupportedOperationException("Not available on ImmutableSortedMap.Builder");
    }

    @Override
    public ImmutableSortedMap<K, V> build() {
      return buildOrThrow();
    }

        return delegate().replaceValues(key, values); // copy not synchronized
      }
    }

    @Override
    @CheckForNull
    public Comparator<? super V> valueComparator() {
      synchronized (mutex) {
        return delegate().valueComparator();
      }
    }

    private static final long serialVersionUID = 0;
  }

  private static <E extends @Nullable Object> Collection<E> typePreservingCollection(

        return delegate().replaceValues(key, values); // copy not synchronized
      }
    }

    @Override
    @CheckForNull
    public Comparator<? super V> valueComparator() {
      synchronized (mutex) {
        return delegate().valueComparator();
      }
    }

    private static final long serialVersionUID = 0;
  }

  private static <E extends @Nullable Object> Collection<E> typePreservingCollection(

     */
    @CanIgnoreReturnValue
    @Override
    @Deprecated
    @DoNotCall("Always throws UnsupportedOperationException")
    public final Builder<K, V> orderEntriesByValue(Comparator<? super V> valueComparator) {
      throw new UnsupportedOperationException("Not available on ImmutableSortedMap.Builder");
    }

    @Override
    Builder<K, V> combine(ImmutableMap.Builder<K, V> other) {
      super.combine(other);

     */
    @CanIgnoreReturnValue
    @Override
    @Deprecated
    @DoNotCall("Always throws UnsupportedOperationException")
    public final Builder<K, V> orderEntriesByValue(Comparator<? super V> valueComparator) {
      throw new UnsupportedOperationException("Not available on ImmutableSortedMap.Builder");
    }

    @CanIgnoreReturnValue
    Builder<K, V> combine(ImmutableSortedMap.Builder<K, V> other) {