object,class, data abstraction, encaptulation, inheritance,polymorphism, message passing

1. Principles of OOP
Presented by
D.Seethalakshmi MCA.,M.Phil.,
Assistant Professor
Bon Secours College for women
Thanjavur.

2. Principles of OOP
 Objects
 Classes
 Data abstraction and encapsulation
 Inheritance
 Polymorphism
 Dynamic binding
 Message passing

3. Objects
o The basic run time entities in object oriented system.
 It represent a person, a place, a bank account or any item that the
program has to handle.
Student
Average
Display
Total
Object: Student
DATA
Name
DOB
Marks
FUNCTIONS
Total
Average

4. Classes
 The entire set of data and code of an object can be made of user
defined data types with the help of class.
 Once class has been defined we can create number of object
belongs to that class.
 A class is a collection of object of similar data type.
 Example:
Fruit mango;

5. Data Encapsulation
 The wrapping up of data and functions into a single unit (called Class) is
known as encapsulation.
 Only access those functions which are wrapped in the class.
 The insulation of the data from direct access by the program is called
data hiding and information hiding.

6. Data Abstraction
 It represents essential features without including the background details or
explanations.
 It defined as a list of abstract attributes. Its sometime called data member
because it holds information.
 This functions are called as methods or member functions.
 Abstraction is known as Abstract Data Type(ADT)

7. Inheritance
 Inheritance is the process by which objects of one class acquire the
properties of objects of another class. It supports the concept of
hierarchical classification.
 Bird Flying bird Robin

8. Polymorphism
An operation may exhibit different
behaviors in different instances. The
behavior depends upon the types of
data used in the operation.
Polymorphism, a greek term means
ability to take more than one form.
To be continued…

9. Operator overloading &
Function overloading
 The process of making an operator to exhibit different behaviors in
different instances is known a operator overloading.
 Example: two numbers operation sum
 A single function name to perform different types of tasks is known
as function overloading.

10. Dynamic Binding
 Binding refers to the linking of a procedure call to the code to be
executed in response to the call.
 Dynamic binding (also known as late binding) means that the code
associated with a given procedure call is not known until the time of
the call at run-time.
 It is associated with polymorphism and inheritance.

11. Message passing
 An object- oriented program consists of a set of objects that
communicate with each other.
 Creating classes that define objects and their behavior
 Creating objects from class definitions
 Establishing communication among objects

12. Benefits of OOPs
 Eliminate redundant code and extend the use of exiting
classes.
 The principle of data hiding helps the programmer to build
secure programs
 It is easy to partition the work in a project based on objects.
 Object oriented systems can be easily upgraded from small
to large systems.
 Software complexity can be easily managed.

13. Applications of OOPs
 Real-time systems
 Simulation and modeling
 Object oriented databases
 Hypertext, hypermedia and expertext
 AI and expert systems
 Neural networks and parallel programming
 Decision support and office automation systems
 CIM/CAM/CAD systems

14. Simple C++ program
#include< iostream.h >
#include< conio.h >
int main( )
{
cout<< “c++ is better than c”<<endl;
getch( );
return 0;
}