2. An approach that provides a way of modularizing
programs by creating partitioned memory area for
both data and functions that can be used as templates
for creating copies of such modules on demand.
Object Oriented Programming (OOP)
3. BASIC CONCEPTS OF OBJECTS ORIENTED
PROGRAMMING
OOP
Objects
Classes
Data
Abstracti
on and
Encapsul
ation
Inheritan
ce
Polymor
phism
Dynamic
Binding
Message
Passing
4. Objects are the basic run-time entities in an object-oriented
system.
They may represent a person, a place, a bank account, a table
of data or any item that the program must handle.
The fundamental idea behind object oriented approach is to
combine both data and function into a single unit and these
units are called objects.
Objects means a combination of data and program that
represent some real word entity.
Objects
5. The entire set of data and code of an object can be made a
user-defined data type with the help of a class.
Objects are variables of the type class.
Each object is associated with the data of type class with
which they are created.
A class is thus a collection of objects of similar type.
Classes
6. Abstraction refers to the act of representing essential features
without including the background details or explanations.
Classes use the concept of abstraction and are defined as a list
of abstract attributes such as size , weight and cost and
functions to operate on these attributes.
The attributes are sometimes called data members because
they hold information.
The functions that operate on these data are called member
functions.
Abstraction
7. The wrapping up of data and functions in to a single unit is
known as encapsulation.
The data is not accessible to the outside world and only those
functions which are wrapped in the class can access it.
This insulation of data from the direct access by the program
is called data hiding or information hiding.
Encapsulation
8. Inheritance is the process by which objects of one class acquire the
properties of another class.
Inheritance provides the idea of reusability.
This mean that we can add additional features to an existing class
with out modifying it.
This is possible by designing a new class will have the combined
features of both the classes.
Inheritance
9. Polymorphism means the ability to take more than one form .
An operation may exhibit different behaviour in different instances.
The behaviour depends up on the types of data used in the operation.
The concepts of polymorphism are Operator overloading and Function overloading.
For two numbers, the operator + will give the sum. If the operands are strings, then
the operation would produce a third string by concatenation .
Thus the process of making an operator to exhibit different behaviours in different
instances is known as operator overloading.
Similarly, we can use a single function to perform different tasks which is known as
function overloading.
Polymorphism
11. Dynamic 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 concept.
Dynamic Binding
12. OOP consists of a set of objects that communicate with each other by
sending and receiving information .
A message for an object is a request for execution of a procedure and
therefore will invoke a function in the receiving object that generates
the desired result.
Message Passing