sortedTable.put("", 42, 'x');
    assertThat(sortedTable.columnComparator()).isEqualTo(Ordering.usingToString());
    assertThat(
            ((SortedMap<Integer, Character>) sortedTable.rowMap().values().iterator().next())
                .comparator())
        .isEqualTo(Ordering.usingToString());
  }

  public void testRowKeySetComparator() {

   *
   * <p>The comparator is serializable.
   *
   * <p><b>Java 8+ users:</b> Use {@code Comparator.comparing(Object::toString)} instead.
   */
  public static Ordering<Object> usingToString() {
    return UsingToStringOrdering.INSTANCE;
  }

  /**
   * Returns an arbitrary ordering over all objects, for which {@code compare(a, b) == 0} implies

   *
   * <p>The comparator is serializable.
   *
   * <p><b>Java 8+ users:</b> Use {@code Comparator.comparing(Object::toString)} instead.
   */
  public static Ordering<Object> usingToString() {
    return UsingToStringOrdering.INSTANCE;
  }

  /**
   * Returns an arbitrary ordering over all objects, for which {@code compare(a, b) == 0} implies

  }

  // preserve singleton-ness, so equals() and hashCode() work correctly
  private Object readResolve() {
    return INSTANCE;
  }

  @Override
  public String toString() {
    return "Ordering.usingToString()";
  }

  private UsingToStringOrdering() {}

  @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;

    assertThat(multimap.get("a")).containsExactly(10, 2).inOrder();
    assertEquals(
        Ordering.usingToString(), ((ImmutableSortedSet<Integer>) multimap.get("a")).comparator());
    assertEquals(
        Ordering.usingToString(), ((ImmutableSortedSet<Integer>) multimap.get("z")).comparator());
  }

  private ImmutableSetMultimap<String, Integer> createMultimap() {
    return ImmutableSetMultimap.<String, Integer>builder()

    testComparator(arbitrary, list);
  }

  public void testUsingToString() {
    Ordering<Object> ordering = Ordering.usingToString();
    testComparator(ordering, 1, 12, 124, 2);
    assertThat(ordering.toString()).isEqualTo("Ordering.usingToString()");
    assertThat(reserialize(ordering)).isSameInstanceAs(ordering);
  }

  // use an enum to get easy serializability

    testComparator(arbitrary, list);
  }

  public void testUsingToString() {
    Ordering<Object> ordering = Ordering.usingToString();
    testComparator(ordering, 1, 12, 124, 2);
    assertThat(ordering.toString()).isEqualTo("Ordering.usingToString()");
    assertThat(reserialize(ordering)).isSameInstanceAs(ordering);
  }

  // use an enum to get easy serializability

  private static final Ordering<Invokable<?, ?>> BY_PARAMETERS =
      new Ordering<Invokable<?, ?>>() {
        @Override
        public int compare(Invokable<?, ?> left, Invokable<?, ?> right) {
          return Ordering.usingToString().compare(left.getParameters(), right.getParameters());
        }
      };

  private static final Ordering<Invokable<?, ?>> BY_NUMBER_OF_PARAMETERS =
      new Ordering<Invokable<?, ?>>() {
        @Override

  private static final Ordering<Invokable<?, ?>> BY_PARAMETERS =
      new Ordering<Invokable<?, ?>>() {
        @Override
        public int compare(Invokable<?, ?> left, Invokable<?, ?> right) {
          return Ordering.usingToString().compare(left.getParameters(), right.getParameters());
        }
      };

  private static final Ordering<Invokable<?, ?>> BY_NUMBER_OF_PARAMETERS =
      new Ordering<Invokable<?, ?>>() {
        @Override