📖 Lecture 5: Object-Oriented Programming (OOP)

• OOP Concepts: Designing software based on real-world objects that contain data (attributes) and behaviors (methods) [18].
• Encapsulation: Hiding data by making variables private and providing access through public getter and setter methods. This protects the internal state of the object [21, 22].
• Inheritance: Allows a class (Subclass) to inherit properties and methods from another class (Superclass) using the extends keyword. It promotes code reusability [23].
• Polymorphism: The ability to take multiple forms [18].
  • Compile-time Polymorphism: Achieved via Method Overloading [21].
  • Run-time Polymorphism: Achieved via Method Overriding (a subclass providing a specific implementation of a superclass method) [22].
• Abstraction: Hiding complex implementation details and showing only essential features [24]. Achieved via Abstract Classes (which cannot be instantiated) or Interfaces [24]. An abstract class can have constructors, but a class can only extend one abstract class (while it can implement multiple interfaces) [25].