Encapsulation-Abstraction - Tagged

Introduction to Python

• Topic: Encapsulation and Abstraction

• Instructor: Dr. Ali Sadiq

Learning Outcomes

1. Understand Encapsulation

2. Principles of Encapsulation

3. Importance of Encapsulation

4. Understand Abstraction

5. Examples of Abstraction in daily life

6. Importance in Object-Oriented Programming

7. Access modifiers in Python (Public, Private, Protected)

8. Working with public and non-public attributes

9. Name mangling concept

10. Getters and Setters in Python

11. Defining Getters and Setters in classes

12. Using Python @property decorator

13. Implementation of @property decorator

Encapsulation

Definition

• Encapsulation is a fundamental OOP feature.

• Bundles data members and methods into a single unit (class).

Importance

• Aids in data hiding by organizing data and methods logically.

• Users care about input/output, not internal workings.

• Objects function independently, preventing unauthorized access to data.

Benefits

• Well-defined, readable code

• Prevents accidental changes

• Enhances security

• Promotes code reusability

Abstraction

Concept

• Encapsulation implements Abstraction.

• Hides the complexity of class implementation from the user.

• Users understand what functionality does but not how it works.

Access Modifiers in Python

• Access Levels:

  • Public: Accessible everywhere

  • Protected: Accessible within class and subclass

  • Private: Accessible only within the class

• Achieved using underscores: single for protected, double for private.

Example:

• Access specifiers:

  • Private: Yes (own class), No (derived class or object)

  • Protected: Yes (own and derived classes), No (from object)

  • Public: Yes (all classes)

Getters and Setters

Purpose

• Ensure data encapsulation by controlling access/modification of private attributes.

Getter Method

• Retrieves the value of a private attribute.

• Named typically with a prefix 'get_'.

• Example: get_name() retrieves name attribute.

Setter Method

• Modifies the private attribute's value.

• Named typically with a prefix 'set_'.

• Example: set_age() modifies the age attribute.

@property Decorator

Functionality

• Simplifiesgetter/setter functionality in OOP.

• Provides a way to control access, modification, and deletion of attributes.

Usage

• Defined with @property for getter and @<property>.setter for setter.

Examples

Without Getters and Setters

• A class can lead to uncontrolled access to attribute values.

With Getters and Setters

• Provides a controlled access mechanism with validation.

Conclusion

• Encapsulation and abstraction are essential in ensuring secure, maintainable, and reusable code in Object-Oriented Programming.