Method Overriding in Python
Method overriding allows a subclass to provide a specific implementation for a method that is already defined in its superclass. This is particularly useful when the behavior needs to be extended or modified. Overriding ensures that the method in the subclass has the same name, return type, and parameters as the method in the parent class.
When a method in a subclass has the same signature as a method in its superclass, the subclass method overrides the superclass method. This allows the subclass to provide a specific implementation of the method.
Let's explore an example to understand method overriding in detail:
Example: Method Overriding
class Animal:
# Method in the superclass
def speak(self):
return "Animal speaks"
class Dog(Animal):
# Overriding the method in the subclass
def speak(self):
return "Dog barks"
animal = Animal()
dog = Dog()
print(animal.speak()) # Output: Animal speaks
print(dog.speak()) # Output: Dog barks
Explanation:
In the above example, we have a superclass Animal
with a method speak
that returns the string "Animal speaks"
. The subclass Dog
inherits from Animal
and overrides the speak
method to return "Dog barks"
.
When we create an instance of Animal
and call the speak
method, it returns "Animal speaks"
. However, when we create an instance of Dog
and call the speak
method, it returns "Dog barks"
. This demonstrates how the speak
method in the Dog
class overrides the speak
method in the Animal
class.
Using super()
to Call the Superclass Method
In some cases, we might want to call the overridden method from the superclass in the subclass. This can be done using the super()
function. Here's an example:
class Animal:
def speak(self):
return "Animal speaks"
class Dog(Animal):
def speak(self):
# Calling the superclass method using super()
parent_speak = super().speak()
return parent_speak + " and Dog barks"
dog = Dog()
print(dog.speak()) # Output: Animal speaks and Dog barks
In this example, the speak
method in the Dog
class calls the speak
method from the Animal
class using super()
and then appends additional behavior to it.