Encapsulation in Python

1. Object Oriented
2. Encapsulation in Python

Encapsulation is one of the fundamental concepts in OOP. It describes the idea of bundling data and methods that work on that data within one unit. This puts restrictions on accessing variables and methods directly and can prevent the accidental modification of data.

A class is an example of encapsulation as it encapsulates all the data that is member functions, variables, etc.

Protected Members

Those members of the class that cannot be accessed outside the class but can be accessed from within the class and its subclasses are called protected members.

In python, protected members are created by prefixing the name of the member by a single underscore “_”.

    
class A:
    def __init__(self):
        self._a = 2

class B(A):
    def __init__(self):
        A.__init__(self)
        print("Getting protected member of class A inside Subclass B: ")
        print(self._a)

obj1 = B()
    

Output

Getting protected member of class A inside Subclass B:
2     

Private Members

Private members are those members who are similar to protected members, which is not accessible from outside the class as well as from sub-class.

In python, to define a private member prefix the member name with double underscore “__”.

Example

class A:
    def __init__(self):
        self.__a = 2  # note double underscore


class B(A):
    def __init__(self):
        A.__init__(self)
        print("Getting private member of class A inside Subclass B: ")
        print(self.__a)


obj1 = B()

Output

An error occurs:

AttributeError: 'B' object has no attribute '_B__a'

In case of private members we can use _{ClassName}__{PrivateMember}

class A:
    def __init__(self):
        self.__a = 2  # note double underscore


class B(A):
    def __init__(self):
        A.__init__(self)
        print("Getting private member of class A inside Subclass B: ")
        print(self._A__a)  # changed code


obj1 = B()
    

Output:

2

Note: In Python there is no actual data hiding