Encapsulation with Access Modifiers in Python

Encapsulation in Python

Definition

Encapsulation is the concept of restricting direct access to an object’s data and methods to protect data integrity.

Access Modifiers

• Private: Accessible only within the class.
• Protected: Accessible within the class and its subclasses.
• Public: Accessible from anywhere.

Encapsulation without Access Modifiers

Program:

class Product:
    def __init__(self, name, price):
        # Public attributes (default)
        self.name = name
        self.price = price

    def display_product(self):
        # Method to display product details
        print(f"Product: {self.name}, Price: {self.price}")

p1 = Product("Laptop", 75000)  # Create object
p1.display_product()  # Output: Product: Laptop, Price: 75000
    

Encapsulation with Access Modifiers

Private

Definition: Variables or methods prefixed with __ are private and not accessible directly outside the class.

Program:

class Bank:
    def __init__(self):
        self.__bank_name = "State Bank of India"  # Private attribute

    def get_bank_name(self):
        # Access private attribute within the class
        print(self.__bank_name)

b1 = Bank()  # Create object
b1.get_bank_name()  # Output: State Bank of India
# print(b1.__bank_name)  # Error: Cannot access private attribute directly
    

Protected

Definition: Variables or methods prefixed with _ are protected and can be accessed within the class or its subclasses.

Program:

class University:
    def __init__(self):
        self._university_name = "Anna University"  # Protected attribute

class Department(University):
    def display_university_name(self):
        # Access protected attribute in the subclass
        print(f"Department belongs to: {self._university_name}")

d1 = Department()  # Create subclass object
d1.display_university_name()  # Output: Department belongs to: Anna University
    

Public

Definition: Variables or methods without any prefix are public and accessible from anywhere.

Program:

class Library:
    def __init__(self):
        self.library_name = "Central Library"  # Public attribute

class Section(Library):
    pass  # Inherits everything from Library

s1 = Section()  # Create subclass object
print(s1.library_name)  # Output: Central Library