考虑以下代码片段:packagevehicle;publicabstractclassAbstractVehicle{protectedintspeedFactor(){return5;}}packagecar;importvehicle.AbstractVehicle;publicclassSedanCarextendsAbstractVehicle{publicstaticvoidmain(String[]args){SedanCarsedan=newSedanCar();sedan.speedFactor();AbstractVehiclevehicle=newSedanCar(