What Are the Key Differences Between Inheritance and Polymorphism in Object-Oriented Programming?

What are the main differences between inheritance and polymorphism in Object-Oriented Programming (OOP)?

Inheritance and polymorphism are fundamental concepts in Object-Oriented Programming (OOP) that help in structuring code and promoting code reuse. Although they are often used together, they serve distinct purposes: inheritance is about creating a new class from an existing class, while polymorphism allows for methods to use classes through a common interface, enabling different implementations.

class Animal {\n    void sound() {\n        System.out.println("Animal sound");\n    }\n}\n\nclass Dog extends Animal {\n    void sound() {\n        System.out.println("Bark");\n    }\n}\n\nclass Cat extends Animal {\n    void sound() {\n        System.out.println("Meow");\n    }\n}\n\npublic class TestPolymorphism {\n    public static void main(String[] args) {\n        Animal myDog = new Dog(); // Upcasting\n        Animal myCat = new Cat(); // Upcasting\n        myDog.sound(); // Output: Bark\n        myCat.sound(); // Output: Meow\n    }\n}

Causes

• Inheritance allows one class to inherit properties and behaviors (methods) from another class, promoting code reuse.
• Polymorphism enables methods to operate on objects of different classes, provided they share the same interface or base class.

Solutions

• Use inheritance to create a hierarchy of classes where child classes can inherit common functionality from parent classes.
• Implement polymorphism to allow a single function or method to work with objects of different classes, enhancing flexibility in code structure.

Mistake: Confusing inheritance with polymorphism, thinking they are the same concept.

Solution: Remember that inheritance is about class relationships, while polymorphism focuses on how methods can operate on objects.

Mistake: Not properly utilizing polymorphism in OOP designs, leading to rigid code.

Solution: Use interfaces or abstract classes to allow different implementations of a method, improving flexibility and reducing coupling.