OOP Concepts

OOP Concepts Overview

Object-Oriented Programming (OOP) is a paradigm built around objects rather than functions. C++ supports four core OOP pillars: encapsulation, inheritance, polymorphism, and abstraction.

Encapsulation

Bundling data and methods inside a class while restricting direct access to internal state. This is achieved with private members and public getters/setters.

Inheritance

A derived class inherits members from a base class, promoting code reuse. Use the colon syntax: class Dog : public Animal.

Polymorphism

The ability to present the same interface for different underlying types. Virtual functions allow a derived class to override a base class method.

Abstraction

Hiding complex implementation details and showing only essential features. Abstract base classes with pure virtual functions enforce this contract.

#include <iostream>
using namespace std;

class Animal {
public:
  virtual void speak() {
    cout << "Animal speaks\n";
  }
};

class Dog : public Animal {
public:
  void speak() override {
    cout << "Dog barks\n";
  }
};

int main() {
  Animal* a = new Dog();
  a->speak();
  delete a;
  return 0;
}