@ElementTypesAreNonnullByDefault
public class TreeRangeSet<C extends Comparable<?>> extends AbstractRangeSet<C>
    implements Serializable {

  @VisibleForTesting final NavigableMap<Cut<C>, Range<C>> rangesByLowerBound;

  /** Creates an empty {@code TreeRangeSet} instance. */
  public static <C extends Comparable<?>> TreeRangeSet<C> create() {
    return new TreeRangeSet<>(new TreeMap<Cut<C>, Range<C>>());
  }