@Override
 public void handleEvent(TransitDriverStartsEvent event) {
   try {
     ptVehicles.put(
         event.getVehicleId(), new PTVehicle(event.getTransitLineId(), event.getTransitRouteId()));
     transitDriverIds.add(event.getDriverId());
   } catch (Exception e) {
     System.err.println(e.getStackTrace());
     System.err.println(event.toString());
     ;
   }
 }
 @Override
 public void handleEvent(final TransitDriverStartsEvent event) {
   handleEvent(eventsPerVehicle, event.getVehicleId(), event);
 }