4. Polymorphism

Introduction

• Poly means many and Morph means form.
• A method can behave differently in different situations.
• Examples:
  • Person can be a father, husband, employee, etc
  • Water can be liquid, solid or gas.

Types of Polymorphism -

1. Compile Time / Static Polymorphism / Method Overloading
2. Run Time / Dynamic Polymorphism / Method Overriding

Method Overloading: Multiple methods in the same class with the same name but different parameters. On the basis of RETURN TYPE overloading CAN’T be done.

public class MathOperations {
    int add(int a, int b) {
        return a + b;
    }
 
    double add(double a, double b) {
        return a + b;
    }
}

Method Overriding: A method in a subclass has the same name, return type, and parameters as a method in the parent class.

public class Animal {
    void sound() {
        System.out.println("This is a generic sound.");
    }
}
 
public class Cat extends Animal {
    void sound() {
        System.out.println("The cat meows.");
    }
}
 
public class Main {
    public static void main(String[] args) {
        Animal animal = new Cat();
        animal.sound();  // Outputs: The cat meows.
    }
}