When an instance of Motorcycle is seen as as Vehicle, then it, quite naturally, cannot give you access to Motorcycle‘s unique properties. That’s the point of inheritance. To access them, you have to type-cast the instance: Vehicle v = new Motorcycle(); ((Motorcycle)v).MotorbikeEngineVolume = 250; When you cannot be sure the instance truly is a Motorcycle, … Read more
Your hasAnimals method needs to return a boolean value i.e. true or false based on the value of the type variable. You’re .. kind of on the right track, but you’re not honoring the requirements of the method. It shouldn’t print anything, and it shouldn’t return type because type is an int and not the … Read more
Polymorphism is enforced dynamically (at runtime) based on the actual type of the object that is calling the method. It relies on the ability to assign an object of a subclass to a reference of the superclass. Also, notice that when you have an instance method in a class and you call another method inside … Read more
There must be something wrong with the quiz, the code as written in the question is declaring that MyInt is a subclass of int (or equivalently: that int is the superclass of MyInt), no the other way around. 1 solved Superclass inherits from a subclass. Coursera. Are they crazy? [closed]