Java Polymorphism Quiz

What is polymorphism in Java?

• Ability to define a method multiple times with the same signature

• Capability of one method to perform multiple functions based on the object that it operates on

• Ability of a subclass to inherit methods from a superclass

• Using the same variable name in different classes

Which of the following is an example of polymorphism?

• Overloading methods

• Implementing multiple interfaces

• Overriding methods in subclasses

• Using private access modifiers

Which of these best demonstrates polymorphism?

• Having a method to draw different shapes using the same draw() method

• Creating an array of shapes with each shape requiring a different draw method

• Writing separate methods for each shape

• Drawing all shapes using if-else conditions

Which keyword is used to make a class abstract?

• final

• static

• abstract

• protected

Which of the following is true about abstract classes?

• They cannot have any methods

• They must be instantiated directly

• They can contain both abstract and non-abstract methods

• They cannot have any subclasses

What is achieved by using polymorphism in programming?

• Complexity

• Code duplication

• Code simplification and flexibility

• Unnecessary code usage

If a superclass reference variable refers to a subclass object, which method will execute when called?

• The method in the superclass

• The method in the subclass

• It depends on the runtime environment

• None of the above

An abstract class can have which of the following?

• Only abstract methods

• Only concrete methods

• Both abstract and concrete methods

• Only static methods

What keyword is used to override a superclass method in Java?

• @override

• extends

• implements

• finalize

Which of these classes cannot be instantiated directly?

• Concrete classes

• Subclasses

• Abstract classes

• Static classes