*/
public String semanticHashString(Trip trip) {
HashFunction murmur = Hashing.murmur3_32();
BaseEncoding encoder = BaseEncoding.base64Url().omitPadding();
StringBuilder sb = new StringBuilder(50);
sb.append(encoder.encode(stopPattern.semanticHash(murmur).asBytes()));
if (trip != null) {
TripTimes tripTimes = scheduledTimetable.getTripTimes(trip);
if (tripTimes == null) return null;
sb.append(':');
sb.append(encoder.encode(tripTimes.semanticHash(murmur).asBytes()));