assertEquals(set.comparator(), copy.comparator());
  }

  @GwtIncompatible // SerializableTester
  public void testSingle_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    set.add("e");
    SortedSet<String> copy = SerializableTester.reserializeAndAssert(set);
    assertEquals(set.comparator(), copy.comparator());
  }

  @GwtIncompatible // SerializableTester

 * invoke methods, they invoke methods on the {@code ForwardingNavigableSet}.
 *
 * <p>Each of the {@code standard} methods uses the set's comparator (or the natural ordering of the
 * elements, if there is no comparator) to test element equality. As a result, if the comparator is
 * not consistent with equals, some of the standard implementations may violate the {@code Set}
 * contract.
 *

      return notSubtype(shop);
    }

    @TestSubtype(suppressGetSubtype = true)
    public Comparator<Electronics> supertypeIsTopLevelClass(
        Mall<Indoor>.Retailer<Electronics> shop) {
      return isSubtype(shop);
    }

    @TestSubtype
    public Comparator<Electronics> topLevelClassIsNotSupertypeDueToTypeParameter(
        Mall<Indoor>.Retailer<Grocery> shop) {

   * MultimapBuilder#treeKeys()}, may make additional guarantees.
   */
  @Override
  Map<K, Collection<V>> asMap();

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

        activeDependencies.removeAll(finishedProjects);
        return activeDependencies;
    }

    /**
     * Gets the smart project comparator used for critical path scheduling.
     *
     * @return the project comparator
     */
    public SmartProjectComparator getProjectComparator() {
        return projectComparator;
    }

    /** Constructor for use by subclasses. */
    public StandardElementSet() {
      super(ForwardingSortedMultiset.this);
    }
  }

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

  @Override
  public SortedMultiset<E> descendingMultiset() {
    return delegate().descendingMultiset();
  }

  /**

   * FluentIterable} in the order specified by {@code comparator}. To produce an {@code
   * ImmutableList} sorted by its natural ordering, use {@code toSortedList(Ordering.natural())}.
   *
   * <p><b>{@code Stream} equivalent:</b> pass {@link ImmutableList#toImmutableList} to {@code
   * stream.sorted(comparator).collect()}.
   *
   * @param comparator the function by which to sort list elements

   * FluentIterable} in the order specified by {@code comparator}. To produce an {@code
   * ImmutableList} sorted by its natural ordering, use {@code toSortedList(Ordering.natural())}.
   *
   * <p><b>{@code Stream} equivalent:</b> pass {@link ImmutableList#toImmutableList} to {@code
   * stream.sorted(comparator).collect()}.
   *
   * @param comparator the function by which to sort list elements

   * {@code ImmutableList}, use {@code stream.sorted(comparator).collect(toImmutableList())}.
   *
   * @throws NullPointerException if any element in the input is null
   * @since 21.0
   */
  public static <E> ImmutableList<E> sortedCopyOf(
      Comparator<? super E> comparator, Iterable<? extends E> elements) {
    checkNotNull(comparator);
    @SuppressWarnings("unchecked") // all supported methods are covariant

    return tmp.toArray(new String[0]);
  }

  static <T> Comparator<T> arbitraryNullFriendlyComparator() {
    return new NullFriendlyComparator<>();
  }

  private static final class NullFriendlyComparator<T> implements Comparator<T>, Serializable {
    @Override
    public int compare(T left, T right) {
      return String.valueOf(left).compareTo(String.valueOf(right));
    }
  }