public DBFixture addEngine(EngineType engineType) {
   currentEngine = new Engine();
   engines.add(currentEngine);
   currentEngine.setType(engineType);
   currentVehicle.setEngine(currentEngine);
   currentEngine.setManufacturer(currentManufacturer);
   return this;
 }
 private DBFixture setConstructionDate(Date date) {
   currentVehicle.setConstructionDate(date);
   return this;
 }
 public Vehicle buildVehicle(String model) {
   Vehicle vehicle = new Vehicle();
   vehicle.setModel(model);
   return vehicle;
 }
 public DBFixture setNettoPrice(Double nettoPrice) {
   currentVehicle.setNettoPrice(nettoPrice);
   return this;
 }
 public DBFixture setModelName(String modelName) {
   currentVehicle.setModel(modelName);
   return this;
 }