assertEquals(
        Collections.reverseOrder(), ((ImmutableSortedSet<Integer>) multimap.get("a")).comparator());
    assertTrue(multimap.get("x") instanceof ImmutableSortedSet);
    assertEquals(
        Collections.reverseOrder(), ((ImmutableSortedSet<Integer>) multimap.get("x")).comparator());
    assertTrue(multimap.asMap().get("a") instanceof ImmutableSortedSet);
    assertEquals(

    assertEquals(comparator, elementSet.comparator());
  }

  private static final Comparator<String> DEGENERATE_COMPARATOR =
      new Comparator<String>() {
        @Override
        public int compare(String o1, String o2) {
          return o1.length() - o2.length();
        }
      };

  /** Test a TreeMultiset with a comparator that can return 0 when comparing unequal values. */

   * the given {@code comparator}.
   *
   * @see #testComparator(Comparator, List)
   */
  public static <T extends @Nullable Object> void testComparator(
      Comparator<? super T> comparator, T... valuesInExpectedOrder) {
    testComparator(comparator, Arrays.asList(valuesInExpectedOrder));
  }

  /**

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;
import java.util.Comparator;
import java.util.SortedSet;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

                new TestStringSortedMapGenerator() {
                  private final Comparator<String> comparator = NullsBeforeTwo.INSTANCE;

                  @Override
                  protected SortedMap<String, String> create(Entry<String, String>[] entries) {
                    SortedMap<String, String> map = new SafeTreeMap<>(comparator);
                    for (Entry<String, String> entry : entries) {

    Ordering<@Nullable Object> comparator = Ordering.allEqual();
    assertSame(comparator, comparator.reverse());

    assertEquals(0, comparator.compare(null, null));
    assertEquals(0, comparator.compare(new Object(), new Object()));
    assertEquals(0, comparator.compare("apples", "oranges"));
    assertSame(comparator, reserialize(comparator));
    assertEquals("Ordering.allEqual()", comparator.toString());

    Ordering<@Nullable Object> comparator = Ordering.allEqual();
    assertSame(comparator, comparator.reverse());

    assertEquals(0, comparator.compare(null, null));
    assertEquals(0, comparator.compare(new Object(), new Object()));
    assertEquals(0, comparator.compare("apples", "oranges"));
    assertSame(comparator, reserialize(comparator));
    assertEquals("Ordering.allEqual()", comparator.toString());

  abstract SortedMultiset<E> forwardMultiset();

  @Nullable private transient Comparator<? super E> comparator;

  @Override
  public Comparator<? super E> comparator() {
    Comparator<? super E> result = comparator;
    if (result == null) {
      return comparator = Ordering.from(forwardMultiset().comparator()).<E>reverse();
    }
    return result;
  }

    @Override
    protected List<String> create(String[] elements) {
      Comparator<String> comparator = createExplicitComparator(elements);
      ImmutableSet<String> set = ImmutableSortedSet.copyOf(comparator, Arrays.asList(elements));
      return set.asList();
    }
  }

            new long[] {GREATEST, GREATEST - (long) 1},
            new long[] {GREATEST, GREATEST},
            new long[] {GREATEST, GREATEST, GREATEST});

    Comparator<long[]> comparator = UnsignedLongs.lexicographicalComparator();
    Helpers.testComparator(comparator, ordered);
  }

  public void testSort() {
    testSort(new long[] {}, new long[] {});
    testSort(new long[] {2}, new long[] {2});