This tutorial covers: -Procedural Vs Object Oriented Programming - OOPS concepts || Object Oriented Programming Concepts 1. OBJECT 2. CLASS 3. ABSTRACTION 4. ENCAPSULATION 5. INHERITANCE 6. POLYMORPHISM 7. DYNAMIC BINDING 8. MESSAGE PASSING

1. JAVA
Object Oriented Programming
Concepts

2. Topics for Today’s Session

3. Initially developed
by
James Gosling
at
Sun Microsystems
and
released
in
1995.
JAVA

4. Object Oriented Programming
 Object oriented Programming is a modern programming method
to design a program using Classes and Objects
Objects
Real world entities that has their own
properties and behaviours such as
Book, Chair, Car, Pen, Table, etc.,
Class
A class is a blueprint or prototype from
which objects are created.
 Major objective is to eliminate unfavorable features
encountered in Procedural approach

5. Procedural Vs Object Oriented ProgrammingProcedural Programming:
 It is known as POP
 Top Down Approach
 It deals with Algorithms
 Divided into functions
 It needs very less memory
 Doesn’s have Access Modifiers
 Data can move freely from function to function in the system
 It is Less Secure
Example: C, Fortran
Object Oriented Programming:
 It is known as OOP
 Bottom Up Approach
 It deals with data
 Divided into Objects
 It needs more memory that of POP
 Has Access Modifiers
 Objects can move & communicate with each other through member functions
 It is more Secure
Example: C++, JAVA, C#

6. Object Oriented Paradigm features
 Emphasis is on data rather than procedure.
 Programs are divided into what are known as objects.
 Data structures are designed such that they characterize the
objects.
 Methods that operate on the data of an object are tied
together in the data structure.
 Data is hidden and cannot be accessed by external functions.
 Objects may communicate with each other through methods.
 New data and methods can be easily added whenever
necessary.
 Follows bottom up approach in program design.
 First, the individual base elements of a program are specified.
 Then they are linked together to form larger sub sytems.

7. Applications of OOP
 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

8. What is Java?
 Java is a computing platform for application development
and an object-oriented,
 Class-based and Concurrent programming language
 It means many statements can be executed at the same time
instead of sequentially executing it.
 Java can run on all platforms and free to access.
 It is platform-independent
 Java is Simple, Secure, Robust, Complete Object oriented
and Platform Independent High level Language
 It is Portable and Multi-thread technology gives High
Performance.
 It supports concurrency
 means the code can be executed by multiple processes at
the same time.

11. OOPS Concepts
 OBJECT ORIENTED PROGRAMMING (OOP) is a programming
concept that works on the principles of abstraction, encapsulation,
inheritance, and polymorphism
 It allows users to create the objects that they want and then,
create methods to handle those objects.
 The basic concept of OOPs is to create objects, re-use them
throughout the program, and manipulate these objects to get
results.
 Object Oriented Programming popularly known as OOP, is used in a
modern programming language like Java
Object-oriented programming has several advantages over procedural
programming:
 OOP is faster and easier to execute
 OOP provides a clear structure for the programs
 OOP helps to keep the Java code DRY "Don't Repeat Yourself", and
makes the code easier to maintain, modify and debug
 OOP makes it possible to create full reusable applications with less
code and shorter development time

12. OOP simplifies software development and maintenance by
providing some concepts:
1. Object
2. Class
3. Inheritance
4. Polymorphism
5. Abstraction
6. Encapsulation
7. Dynamic Binding
8. Message Passing

13. Object:
 An instance of a class is known as a Object.
 Objects are the basic runtime entities in an object oriented
system.
 Real world entity that has state and behavior .
For example, a chair, pen, table, keyboard, bike, etc. It can be
physical or logical.
 An object contains an address and takes up
some space in memory.
 Each object contains data and code to
manipulate the data.
Representing an object

14. Class
 A class is a blueprint or prototype from which objects
are created.
 Collection of objects.
 It is a logical entity not the physical entity
 The class is a group of similar entities.
For example, if a class is “Expensive Cars”
then objects like Mercedes, BMW, Toyota, etc.
Its properties(data) can be - price, model or speed etc.,
Methods - driving, reverse, braking etc.
Two instances of the class Student

15.  Classes and objects are the two main aspects of object-
oriented programming.
 So, a class is a template for objects, and an object is an
instance of a class.
 When the individual objects are created, they inherit all
the variables and methods from the class.

16. Data Abstraction
 Hiding internal details and showing functionality is known
as abstraction.
For example phone call, we don't know the internal
processing.
 Abstraction refers to the act of representing essential
features without including the background details or
explanations.
 Classes use the concept of abstraction and they are known
as abstract data types (ADT).
 Classes are defined as a list of abstract attributes such as
size, weight and cost and methods that operate on these
attributes.
 The technique of creating new data types that are well
suited to an application to be programmed is known as Data
Abstraction
 In Java, we use abstract class and interface to achieve
abstraction.

17. Encapsulation
 Encapsulation means “Combining”.
 The wrapping up of data and methods into a
single unit (called class) is known as
Encapsulation.
For example - in school, a student cannot exist
without a class.
Capsule

18. Inheritance
 Inheritance involves the creation of new classes (derived classes) from the
existing ones ( base classes ).
 It is the process by which object of one class acquire the properties of
another class.
 It supports the concept of hierarchical classification.
Example: The bird Robin is a part of the class flying bird which is
again a part of the bird
 Provides code reusability.
 Used to achieve runtime
Polymorphism

19. o Single Inheritance refers to deriving a class from a single
class.
o A class is derived from more than one base class is known as
Multiple inherence.

20. Polymorphism
 It is a Greek term, “Poly” means “many” and “morph” means
“form”.
 Polymorphism means the ability to take more than one form.
 When one task is performed by different ways
 An operation may exhibit different behaviors in different
instances.
 The behavior depends upon
the types of data used in the
operation.

21.  There are 2 types of Polymorphism:
1. Compile-time Polymorphism (Method overloading / Static)
2. Runtime Polymorphism (Method Overriding / Dynamic)
Method overloading
 Having multiple methods with same name but with
different signature (number, type and order of
parameters).
Method Overriding
 When a subclass contains a method with the same name
and signature as in the super class .

22. Dynamic Binding
 Binding refers the linking of a procedure call to the code
to be executed in response to the call.
 Dynamic binding means that the code associated with a
given procedure call is not known until the time of the
call at runtime.
 It is associated with polymorphism & inheritance.

23. Message Passing
 A Message for an object is a request for execution of a
procedure .
 It is the process of invoking an operation on an object.
 It involves the name of the object, the name of the
method (message) and the information to be sent.
For Example: Employee. salary (name);
Here, Employee is the object,
salary is the message and
name is the parameter that contains information.

24. Summary

25. Conclusion
 In this lesson you learnt about
 Object Oriented Programming
 Procedural Vs Object Oriented Programming
 Object Oriented Paradigm
 Applications of OOP
 What is Java?
 OOPs Concepts