ImmutableSortedMap<String, Integer> map =
        ImmutableSortedMap.<String, Integer>naturalOrder().build();
    assertEquals(Collections.<String, Integer>emptyMap(), map);
  }

  public void testSingletonBuilder() {
    ImmutableSortedMap<String, Integer> map =
        ImmutableSortedMap.<String, Integer>naturalOrder().put("one", 1).build();
    assertMapEquals(map, "one", 1);
  }

  public void testBuilder() {

    @Override
    public SortedMap<String, String> create(Entry<String, String>[] entries) {
      ImmutableSortedMap.Builder<String, String> builder = ImmutableSortedMap.naturalOrder();
      for (Entry<String, String> entry : entries) {
        checkNotNull(entry);
        builder.put(entry.getKey(), entry.getValue());
      }
      return builder.build();
    }
  }

    @Override
    public SortedMap<String, String> create(Entry<String, String>[] entries) {
      ImmutableSortedMap.Builder<String, String> builder = ImmutableSortedMap.naturalOrder();
      for (Entry<String, String> entry : entries) {
        checkNotNull(entry);
        builder.put(entry.getKey(), entry.getValue());
      }
      return builder.build();
    }
  }

  /**
   * Not supported. Use {@link #naturalOrder}, which offers better type-safety, instead. This method
   * exists only to hide {@link ImmutableSet#builder} from consumers of {@code ImmutableSortedSet}.
   *
   * @throws UnsupportedOperationException always
   * @deprecated Use {@link ImmutableSortedSet#naturalOrder}, which offers better type-safety.
   */
  @DoNotCall("Use naturalOrder")
  @Deprecated

    assertThat(set).containsExactly(101, 12, 3, 44).inOrder();
  }

  @Override
  <E extends Comparable<E>> ImmutableSortedSet.Builder<E> builder() {
    return ImmutableSortedSet.naturalOrder();
  }

  @Override
  int getComplexBuilderSetLastElement() {
    return 0x00FFFFFF;
  }

  public void testLegacyComparable_of() {

  }

  private static final Comparator<?> NATURAL_ORDER = Ordering.natural();

  // TODO(b/345814817): Move this to RegularImmutableSortedSet?
  @SuppressWarnings({"unchecked", "ClassInitializationDeadlock"})
  private static final ImmutableSortedSet<Object> NATURAL_EMPTY_SET =
      new RegularImmutableSortedSet<Object>(
          new TreeSet<Object>((Comparator<Object>) NATURAL_ORDER), false);

              + " and "
              + key
              + "="
              + value);
    }
    map.put(key, value);
  }

  public static <K extends Comparable<?>, V> Builder<K, V> naturalOrder() {
    return new Builder<K, V>(Ordering.natural());
  }

  public static <K, V> Builder<K, V> orderedBy(Comparator<K> comparator) {
    return new Builder<K, V>(comparator);
  }

 *       how the collection was created. Typically this is insertion order unless an explicit
 *       ordering is otherwise specified (e.g. {@link ImmutableSortedSet#naturalOrder}). See the
 *       appropriate factory method for details. View collections such as {@link
 *       ImmutableMultiset#elementSet} iterate in the same order as the parent, except as noted.

 *       how the collection was created. Typically this is insertion order unless an explicit
 *       ordering is otherwise specified (e.g. {@link ImmutableSortedSet#naturalOrder}). See the
 *       appropriate factory method for details. View collections such as {@link
 *       ImmutableMultiset#elementSet} iterate in the same order as the parent, except as noted.