ArrayList<Vehicle> vehicle_array;
TreeMap<Float, Vehicle> time_vehicle;
Vehicle objv = null;
VtypeprobesType v = elem_v.getValue();
List<TimestepType> timestepList = v.getTimestep();
for(TimestepType timeS:timestepList){// scorro tempi
//System.out.println(System.currentTimeMillis()+" inizio parse tempo: "+timeS.getTime());
if (timeS.getTime() == null) {
throw new MyException("time must exist");