Polymorphism in Java

 

What is Polymorphism?

Polymorphism means “many forms.”
In Java, it allows one object to take many forms — like a parent type being used to refer to child objects.

👉 It makes your code flexible, reusable, and extensible.

Types of Polymorphism

1. Compile-Time Polymorphism (Method Overloading)

2. Run-Time Polymorphism (Method Overriding)

1. Compile-Time Polymorphism – Method Overloading

Same method name, different parameters (in same class).

class MathUtils {

    int add(int a, int b) {

        return a + b;

    }

    double add(double a, double b) {

        return a + b;

    }

}

 2. Run-Time Polymorphism – Method Overriding

A child class redefines a method from its parent.

Example:

class Animal {

    void makeSound() {

        System.out.println("Some sound");

    }

}

class Dog extends Animal {

    void makeSound() {

        System.out.println("Bark");

    }

}

Animal a = new Dog();

a.makeSound();  // Output: Bark