1Z0-811 Inheritance and Polymorphism 2

Question 1

What is method overriding in Java?

Accepted Answer

Providing a new implementation of a parent class method in a subclass

Answer

Defining a method with the same name but different parameters in the same class

Answer

Calling a parent method using the super keyword

Answer

Hiding a static method from a parent class

Question 2

Which annotation should be used when overriding a method to catch signature errors at compile time?

Accepted Answer

@Override

Answer

@Inherited

Answer

@Super

Answer

@Overwrite

Question 3

Can a private method in a parent class be overridden by a subclass?

Accepted Answer

No, private methods are not inherited and cannot be overridden

Answer

Yes, if the subclass is in the same package

Answer

Yes, always

Answer

No, unless the subclass uses the super keyword

Question 4

What is the rule regarding access modifiers when overriding a method?

Accepted Answer

The overriding method must have the same or broader (less restrictive) access modifier

Answer

The overriding method must have the exact same access modifier

Answer

The overriding method can have a more restrictive access modifier

Answer

The overriding method can freely change the access modifier

Question 5

What is runtime polymorphism in Java?

Accepted Answer

Method overriding resolved at runtime based on the actual object type

Answer

Method overloading resolved at compile time

Answer

Using generics to handle multiple types

Answer

Casting one reference type to another at runtime

Question 6

Can a method declared 'final' in a parent class be overridden by a subclass?

Accepted Answer

No, final methods cannot be overridden

Answer

Yes, in any subclass

Answer

Yes, only if the subclass is in the same package

Answer

No, unless the @Override annotation is applied

Question 7

Given Animal ref = new Dog(); where Dog extends Animal and both define speak(), which speak() is called on ref.speak()?

Accepted Answer

Dog's speak() because the actual object is Dog

Answer

Animal's speak() because the reference type is Animal

Answer

Both speak() methods are called sequentially

Answer

A compilation error occurs