Object oriented programming. (1).pptx
- 1. OBJECT ORIENTED PROGRAMMING C++ : Extension of C ( BCA 209 )
- 2. OBJECTIVES OF THE SUBJECT To understand the basic concepts of Object Oriented Programming and their applications. To understand the various programming skills using the OOP features like Objects, Class, Data Abstraction, Encapsulation, Inheritance, Polymorphism. To gain knowledge about the concept of generic programming using templates. To understand the concept of file handling and exception handling.
- 3. • C++ began as an expanded version of the programming language C. The C++ was first invented by Bjarne Stroustrup in 1979 at Bell Laboratories in Murray Hill, New Jersey. • He initially called the language “C with Classes”. However, in 1983 the name was changed to C++. • The invention of C++ was necessitated by one major programming factor i.e. increasing complexity. Even though C is an excellent programming language, it has certain limits. The essence of C++ is to allow the programmer to comprehend and manage larger and more complex programs. INTRODUCTION
- 4. DIFFERENCE BETWEEN C AND C++ • C follows the procedural programming paradigm while C+ + is a multi-paradigm language (procedural as well as object oriented). • The basic difference between C and C++ is in terms of Object Oriented Programming i.e. OOP. • Basically, C++ extends C with Object Oriented Features.
- 5. Procedural and Object Oriented Programming • Procedural programming: focus is on the process. Procedures/functions are written to process data. Ex:- C • Object-Oriented programming: focus is on objects, which contain data and the means to manipulate the data. Messages sent to object to perform operations. Ex:- C++
- 6. #include<stdio.h> #include<iostream.h> void main() void main() { { printf (“hello world n”) ; cout << “hello world n” ; } } C PROGRAM C++ PROGRAM Header Files ( for basic input output ) Write to output screen Output Operator It is used to direct a value to standard output.
- 7. FEATURES OF OOP OBJECTS CLASSES ENCAPSULATION DATA ABSTRACTION INHERITANCE POLYMORPHISM
- 8. OBJECTS Objects are the basic run time entities in an object oriented system. They may represent a person, a place, a bank account etc. that the program has to handle. “Object" refers to a particular instance of a class. Three properties characterize objects: 1. Identity: the property of an object that distinguishes it from other objects 2. State: describes the data stored in the object 3. Behaviour: describes the methods in the object's interface by which the object can be used
- 9. CLASS • In object-oriented programming, a class is a construct that is used to create instances of itself . The entire set of data and code of object can be made a user defined with the help of a class. • In fact, objects are variables of the type class. • For example, if car has been defined as a class then car zen; will create an object zen belonging to the class car.
- 11. General Structure of a class Class name or name of class Data Members Member functions Access Specifiers Declaring objects
- 12. Classes in C++ A class definition begins with the keyword class. The body of the class is contained within a set of braces, {} ; (notice the semi-colon). class class_name { …. …. …. }; Class body (data member + methods) Any valid identifier
- 13. Inside class Class item { int number; Float cost; Public: Void getdata( ) { cout<<“ Enter no”; cin>>numbe r; cout<<“Ente r cost”;
- 14. Access Specifiers Used to specify access rights for the data members and member functions of the class. Depending upon the access level of a class member, access to it is allowed or denied. Within the body, the keywords private: and public: specify the access level of the members of the class. the default is private. Usually, the data members of a class are declared in the private: section of the class and the member functions are in public: section.
- 15. Classes in C++ class class_name { private: … … … public: … … … }; Public members or methods private members or methods
- 16. ENCAPSULATION AND DATAABSTRACTION • The wrapping up of data and functions into a single unit is called Encapsulation. • Example – Class • The data is not accessible to the outside world and only those functions that are wrapped inside the class can access it. This insulation of the data from the direct access by the program is called data hiding or information hiding. • Abstraction refers to the act of representing essential features without including the background details.
- 17. INHERITANCE • Inheritance is the process by which one class acquires the properties of objects of another class. • Inheritance provides the idea of reusability. This means we can add additional features to an existing class without modifying it.
- 18. POLYMORPHISM • Polymorphism, Greek word, means to take more than one forms. • An operation may exist different behaviour in different instances. • Example – function overloading and operator overloading
- 19. OVERVIEWOFTHESYLLABUS 1st Unit • Introduction to the Object-Oriented Approach, Features of Procedure oriented programming. • Basic Concepts of Object Oriented Programming • Benefits of OOP • Applications of OOP • Difference between C and C++ • cin, cout operators • C++ standard libraries • Introduction to various C++ compilers
- 20. 2nd Unit • Classes and Objects • Encapsulation, information hiding • C++ class declaration • C++ classes: Attributes and methods • Function Overloading: implementation • Constructors and destructors • C++ garbage collection, dynamic memory allocation • Meta class/abstract classes
- 21. 3rd Unit • Inheritance and Polymorphism: Detail programming • Types of Inheritance • Class hierarchy, derivation – public, private & protected • Aggregation, composition v/s classification hierarchies • Polymorphism: Categorization of polymorphism techniques, Method polymorphism, Polymorphism by parameter • Operator overloading: Implementation • Early v/s Late Binding
- 22. 4th Unit • Generic Programming – Introduction, templates • Template functions, Overloading of template • Functions • Files and Exception Handling • Streams and files • Namespaces, The basic stream classes: C++ predefined streams • Error handling during file operations • Types of Exception, Catching and Handling Exceptions
- 23. Text Book • E. Balguruswamy, “C++ ”, TMH Publication ISBN 0-07- 462038-x • A.R.Venugopal, Rajkumar, T. Ravishanker “Mastering C++”, TMH, 1997 Reference Book Schildt Herbert, “C++: The Complete Reference”, 4th Ed., Tata McGraw Hill, 1999 REFERENCE MATERIAL
- 24. THANK YOU