/**
 * An ordering that treats all references as equals, even nulls.
 *
 * @author Emily Soldal
 */
@GwtCompatible
final class AllEqualOrdering extends Ordering<@Nullable Object> implements Serializable {
  static final AllEqualOrdering INSTANCE = new AllEqualOrdering();

  @Override
  @SuppressWarnings("UnusedVariable") // intentionally weird Comparator
  public int compare(@Nullable Object left, @Nullable Object right) {