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Saif Uddin
Saif Uddin

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πŸ’» Mastering Java OOP: Understanding Classes, Objects, and the Four Pillars

πŸ” Description:

This post introduces Java’s Object-Oriented Programming model by breaking down the four fundamental principles β€” Encapsulation, Inheritance, Polymorphism, and Abstraction β€” with real-world analogies and simple code examples. It also walks through how classes and objects work in Java, making it easy for readers to apply the concepts in their own projects.

πŸ” Encapsulation

Encapsulation is the concept of hiding internal data and only exposing what’s necessary through methods. It protects an object's state and promotes modular code.
πŸ‘‰ Example: Using private fields and public getters/setters.

🧬 Inheritance

Inheritance allows a class (subclass) to acquire properties and behaviors from another class (superclass), promoting code reuse and hierarchy.
πŸ‘‰ Example: A Dog class can inherit from an Animal class.

πŸŒ€ Polymorphism

Polymorphism lets one interface or method behave differently based on the object that calls it. It supports method overloading and overriding.
πŸ‘‰ Example: A method draw() behaves differently for Circle and Rectangle.

🧩 Abstraction

Abstraction is about hiding complex implementation details and showing only the essential features of an object. Achieved through abstract classes and interfaces.
πŸ‘‰ Example: You interact with a List interface, not worrying whether it's an ArrayList or LinkedList.

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