Abstraction

Abstraction is the concept of hiding complex implementation details and showing only the essential features of an object. It helps reduce complexity and increase efficiency by allowing users to interact with objects at a higher level without worrying about internal implementation.

Understanding Abstraction

Abstraction focuses on what an object does rather than how it does it. It provides a simplified interface to complex systems.

Real-World Analogy

Think of a car:

• What you see: Steering wheel, pedals, gear shift
• What’s hidden: Engine mechanics, transmission system, fuel injection

You don’t need to know how the engine works to drive the car - that’s abstraction!

Abstract Base Classes (ABC)

Abstract classes cannot be instantiated directly and must be subclassed. They define a contract that subclasses must follow.

Basic Abstract Class

classDiagram
    class Shape {
        <<abstract>>
        +area()* float
        +perimeter()* float
        +describe() str
    }
    
    class Rectangle {
        -width: float
        -height: float
        +area() float
        +perimeter() float
    }
    
    class Circle {
        -radius: float
        +area() float
        +perimeter() float
    }
    
    Shape <|-- Rectangle
    Shape <|-- Circle
    
    note for Shape "Abstract class\nCannot be instantiated"

Real-World Example: Payment Processing

Abstract Properties

You can also define abstract properties:

Benefits of Abstraction

Why Abstraction Matters

Abstraction provides several key benefits:

1. Simplifies Complexity - Users don’t need to understand implementation details
2. Enforces Interface - Ensures all subclasses implement required methods
3. Flexibility - Easy to swap implementations
4. Maintainability - Changes to implementation don’t affect the interface
5. Code Reuse - Common functionality can be shared in the abstract class

Example: Database Abstraction

Key Takeaways

Remember

• Abstraction hides implementation details and exposes only essential features
• Abstract classes cannot be instantiated - they define a contract for subclasses
• Abstract methods must be implemented by subclasses
• Concrete methods in abstract classes can be shared by all subclasses
• Abstract properties can also be defined using @property and @abstractmethod

• Use abstraction to create flexible, maintainable code that can work with multiple implementations

Abstraction is about creating a contract that all implementations must follow, while hiding the complexity of how each implementation works internally.