OOS Concept

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• CObject Oriented Programming

Sumit Agarwal
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Todays session we will review

• What is Programming Language?
• What is OOP?
• Why OOP?
• Keys to OO programming
• Why C?
• Constructors
• Types of Constructor
• References

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What Is Programming Language?

• A programming language specifies the words and
  symbols that we can use to write a program.
• C was developed by sir stroustrup at AT T
  Bell Lab. USA in early 1980s.
• Major programming paradigm are
• Procedure-Oriented Programming
• Object-Oriented Programming

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What Is POP?

• Procedure-Oriented Programming is a philosophy
  where the source code of a program is split into
  functions.
• Employs Top-Down Approach.
• Lack of Data Hiding Concept.
• Some examples of POP Languages are
• C
• Visual Basic
• Fortran

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POP HYPOTHESIS

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What Is OOP?

• Object-Oriented Programming is a philosophy
  where the source code of a program is split into
  reusable objects.
• An instance of a class is know as an Object.
• Languages that are based on classes are know as
  object-oriented.
• C
• Java

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OOP HYPOTHESIS

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Why Object Oriented Programming?

• Employs Bottom-Up Approach.
• Provides Fault Containment.
• Cant use components (e.g., a class) in
  inappropriate ways.
• Provides Independence between Components.
• Design/development can be done by more than one
  person.

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Keys To OO Programming

• Class
• Object
• Data Abstraction Encapsulation
• Inheritance
• Polymorphism
• Dynamic Binding
• Message Passing

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Why C?

• The main aim of C is to create user defined
  data types such as class. This means we should be
  able to initialize a class type variable(object)
  when it is declared and when a variable of built
  in types goes out of scope, the compiler
  automatic destroys the variable.
• C provides a special member function for the
  above purpose called Constructor and Destructor
  respectively.

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The Interface In C

• class Car
• public
• // visible to all the functions/methods in
  program.
• protected
• // Visible to member function/method with in
  its own and derived class.
• private
• // Visible to member function/method with in
  its class.

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Reasons For Using C

• Bandwagon effect  
• Low-level and high-level features
• Superset of C language
• Efficient implementation
• Multi paradigm language

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Constructors

• It is a special member function with the same
  name as its class which enables an object to
  initialize itself.
• A constructor is called automatically whenever a
  new instance of a class is created.
• If we do not specify a constructor, the compiler
  generates a default constructor for us (expects
  no parameters and has an empty body).

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Characteristics Of Constructors

• Constructor should be declared in the public
  section.
• Constructor can not be inherited.
• They do not have return types, not even void and
  therefore they can not return values.
• They are invoked automatically when the object
  are created.
•  

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Types of Constructor

• Default Constructor A constructor that accept no
  argument is called default constructor.
• Example studentstudent() is default
  constructor.  
• class student
• int roll_no
• public
• student() //Default
  constructor
• roll_no105

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Parameterized Constructor

• Parameterized Constructor The constructor that
  can take arguments are called parameterized
  constructor.
• class student
• int roll_no
• public
• student(int x)
  //Parameterized constructor
• roll_nox
•  

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Copy Constructor

• Copy Constructor The copy constructor is used to
  declare and initialized the object from another
  object.
• class student
• int roll_no
• public
• student(int x)
  //Parameterized constructor
• roll_nox
• student(student s)
•  

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Copy Constructor(Contd.)

• roll_nos.roll_no
• void display()
• coutltltroll_no
•  void main()
• student x(100)
• student y(x)
• x.display()
• y.display()

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References

• Graham Learning C(TMH)
• E. Balagurusamy- Object Oriented Programming with
  C(TMH)
• Bjarne Stroustrup- C Programming Language
  (Addison
  Wesley)
• http//www.cplusplus.com
•  

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THANK YOU!!!

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