Features of Object Oriented Programming Part 2 | C ++ Tutorial | Mr. Kishore

Summary

This video script by Kishore from Nares introduces the fundamental concepts of Object-Oriented Programming (OOP). It explains the core features of OOP, such as classes, objects, data hiding, encapsulation, inheritance, and polymorphism. The script delves into the comparison between C structures and C++ classes, highlighting the extension of structures into classes with added benefits like data protection and the ability to design complex applications. It also clarifies the difference between structures and classes in C++, emphasizing the private access specifier in classes for secure data handling and the role of member functions in accessing private data, encapsulating the principles of data hiding and encapsulation.

Takeaways

• 😀 Object-Oriented Programming (OOP) is a programming paradigm that uses 'classes' and 'objects' to design applications.
• 🏫 The concept of 'class' in OOP is an extension of the C structure, allowing the bundling of data and functions together.
• 🔒 Data hiding in OOP is achieved by using private access specifiers, restricting access to class data members to only member functions within the same class.
• 📦 Encapsulation is the process of binding data and associated functions into a single unit, which is the class, providing a way to bundle data and methods that operate on the data.
• 🔑 Inheritance is a key feature of OOP that allows a new class to inherit properties and behaviors (methods) from an existing class.
• 📈 Polymorphism allows objects to be treated as instances of their parent class rather than their actual class, enabling a single interface to be used for a general class of actions.
• 🔄 Message communication is the mechanism by which objects interact with each other in OOP, typically through method calls.
• 📌 The 'structure' in C language is a collection of heterogeneous variables and is the foundation for OOP concepts, but lacks data protection and complex program design capabilities.
• 🔄 C++ extends the concept of structures by allowing the declaration of member functions and access specifiers, but still has the limitation of public data by default.
• 🛡️ The introduction of 'class' in C++ addresses the shortcomings of structures by providing private, protected, and public access levels, enhancing data security and supporting complex program design.
• 🔍 An object in OOP is an instance of a class, representing the physical manifestation of the class blueprint, with allocated memory for its data members when created.

Q & A

What does OOP stand for and what are its main features?

OOP stands for Object-Oriented Programming. Its main features include class, object, data hiding, encapsulation, inheritance, polymorphism, and message communication.

What is a class in the context of OOP?

A class in OOP is an extension of a C structure. It is a user-defined data type that allows the bundling of data and functions together into a single unit, which can then be used to create objects.

What is the difference between a C structure and a C++ structure?

In C, structures can only contain variables, whereas in C++, structures can also contain member functions along with variables. However, by default, both C and C++ structures have public data members, which can be accessed from anywhere in the program.

Why were classes introduced in C++?

Classes were introduced in C++ to address the issue of data protection that is not available in structures. Classes allow for the encapsulation of data and functions, and they support access specifiers like private, which restrict access to class members from outside the class.

What is the concept of data hiding in OOP?

Data hiding in OOP is the practice of making class data members private, so they can only be accessed and modified by the class's member functions. This prevents unauthorized access and modification of the data from outside the class.

What is encapsulation and how is it achieved in a class?

Encapsulation is the process of binding data and the associated functions together into a single unit or class. It is achieved by declaring data members and member functions within a class and using access specifiers to control access to these members.

What is an object in OOP?

An object in OOP is an instance of a class. It is a variable of the class type and represents the physical manifestation of the class blueprint, holding actual data and being able to perform actions defined by its member functions.

How does a class act as a blueprint for creating objects?

A class acts as a blueprint by defining the structure and behavior of the objects that can be created from it. When an object is instantiated from a class, memory is allocated for the object's data members, and the object can access the class's member functions.

What is the default access level for members in C++ classes and structures?

In C++, the default access level for members in a class is private, whereas in C++ structures, the default access level is public.

Why are structures not suitable for designing large applications?

Structures are not suitable for designing large applications because they do not support the concept of inheritance, which is crucial for creating extensible and maintainable code in large projects. Classes, on the other hand, support inheritance along with encapsulation and data hiding.

Can you access private data members of a class from outside the class?

No, private data members of a class cannot be accessed from outside the class. They can only be accessed and modified through the class's member functions, ensuring data hiding and encapsulation.