toMap method Null safety

Implementation

@override
Map<String, Object?> toMap() {
  return {
    'name': this.name,
    'departureStation': this.departureStation,
    'arriveTime': this.arriveTime,
    'departureTime': this.departureTime,
    'arriveStation': this.arriveStation,
    'passStationNum': this.passStationNum,
    'firstTime': this.firstTime,
    'lastTime': this.lastTime,
    'type': this.type,
  };
}