Polymorphism
Computer Science: OCR A Level, topic 2.4.12
Polymorphism
In object-oriented programming, polymorphism is when a subclass alters its inherited methods in two ways: by overloading or overriding.
Overloading
- Overloading is when a method is defined in the subclass that has the same name, but different arguments to a method defined in the superclass.
- The method might also have a different return type.
- For example, a shape superclass might have an area calculating function.
- The subclass circle could have the function area(radius), whereas a triangle subclass could have the function area(base,height).
Overriding
- Overriding is when a method is redefined in the subclass with the same name and same arguments.
- The method that is defined in the subclass overrides the method defined in the super class.
Test yourself on Polymorphism
What is the term used for when a subclass alters its inherited methods?
Which property must be the same when overloading a method in a subclass?