return subMap(Range.downTo(fromKey, BoundType.forBoolean(inclusive)));
    }

    @Override
    public Comparator<? super Cut<C>> comparator() {
      return Ordering.<Cut<C>>natural();
    }

    @Override
    public boolean containsKey(@CheckForNull Object key) {
      return get(key) != null;
    }

    @Override
    @CheckForNull

 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeSet<E> implements Serializable, NavigableSet<E> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      new Comparator<Object>() {
        @Override
        public int compare(Object o1, Object o2) {
          return ((Comparable<Object>) o1).compareTo(o2);
        }
      };

                new TestStringSetGenerator() {
                  @Override
                  protected Set<String> create(String[] elements) {
                    SafeTreeSet<String> set = new SafeTreeSet<>(Ordering.natural().nullsFirst());
                    Collections.addAll(set, elements);
                    return new StandardImplForwardingNavigableSet<>(set);
                  }

                  @Override

  @Parameters(name = "allowsSelfLoops={0}, allowsParallelEdges={1}, nodeOrder={2}, edgeOrder={3}")
  public static Collection<Object[]> parameters() {
    ElementOrder<?> naturalElementOrder = ElementOrder.sorted(Ordering.natural());

    return Arrays.asList(
        new Object[][] {
          {false, false, ElementOrder.insertion(), ElementOrder.insertion()},
          {true, false, ElementOrder.insertion(), ElementOrder.insertion()},

    checkNotNull(other);
    checkArgument(this.domain.equals(other.domain));
    if (other.isEmpty()) {
      return other;
    } else {
      C lowerEndpoint = Ordering.<C>natural().max(this.first(), other.first());
      C upperEndpoint = Ordering.<C>natural().min(this.last(), other.last());
      return (lowerEndpoint.compareTo(upperEndpoint) <= 0)
          ? ContiguousSet.create(Range.closed(lowerEndpoint, upperEndpoint), domain)

 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public final class SafeTreeSet<E> implements Serializable, NavigableSet<E> {
  @SuppressWarnings("unchecked")
  private static final Comparator<Object> NATURAL_ORDER =
      new Comparator<Object>() {
        @Override
        public int compare(Object o1, Object o2) {
          return ((Comparable<Object>) o1).compareTo(o2);
        }
      };

        builder.orderEntriesByValue(Ordering.natural()).buildOrThrow();
    assertMapEquals(keyOrdered, "four", 4, "one", 1);
    assertMapEquals(valueOrdered, "one", 1, "four", 4);
  }

  public void testBuilder_orderEntriesByValue_usedTwiceFails() {
    ImmutableMap.Builder<String, Integer> builder =
        new Builder<String, Integer>().orderEntriesByValue(Ordering.natural());
    try {

public class SynchronizedNavigableSetTest extends TestCase {

  @SuppressWarnings("unchecked")
  protected <E> NavigableSet<E> create() {
    TestSet<E> inner =
        new TestSet<>(new TreeSet<E>((Comparator<E>) Ordering.natural().nullsFirst()), null);
    NavigableSet<E> outer = Synchronized.navigableSet(inner, null);
    inner.mutex = outer;
    return outer;
  }

    return new AnEnum[length];
  }

  @Override
  public final String[] createValueArray(int length) {
    return new String[length];
  }

  /** Returns the elements sorted in natural order. */
  @Override
  public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {
    return orderEntriesByKey(insertionOrder);
  }

    return new AnEnum[length];
  }

  @Override
  public final String[] createValueArray(int length) {
    return new String[length];
  }

  /** Returns the elements sorted in natural order. */
  @Override
  public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {
    return orderEntriesByKey(insertionOrder);
  }