Object Oriented Programming

Lecture - 5

Revisiting OOP
CS223
CS223- Object Oriented Programming
Spring 2012
Dr. Fawad Hussain

What we have done so far?
What is object-Oriented Programming?
What is an object?
What is a class?
What are attributes?
What are methods?

How to write a simple class in C++.
Constuctors
Default, overloaded, Destructors

But how to identify objects??
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Ghulam Ishaq Khan Institute – Spring 2012

Todays Lecture

Revisiting OOP
Identifying Objects, basics of OO analysis and Design

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OOP

Defining the term
“Object-Oriented”

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Ghulam Ishaq Khan Institute – Spring 2012

What is an Object?
It is something we interact with
It does something, and/or
It knows something

Thinking in Objects
Everything Is an object.
Every object has an Name/Identity.
Every object has a state.
Every object has a behavior.

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Ghulam Ishaq Khan Institute – Spring 2012

Objects in our Business World

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Ghulam Ishaq Khan Institute – Spring 2012

My Object is not Your Object
What you recognize as an object may not be what others recognize as objects Different people can come of with different OO design of the same thing
But there must be some common features and reasoning

Different applications/softwares might treat objects differently

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Ghulam Ishaq Khan Institute – Spring 2012

The world view
Is different depending on who you are
Goes from high level abstraction to low level realizations
The Universe, Solar system, Asia, South Asia, Pakistan, KPK,
Topi, GIK, FCSE, LH3
Video Rental Stores, Blockbusters, Inventory, Action Movies,
“Terminator”
“Terminator”

Why we care?
We use objects to model the system we are trying to create
Objects allow us to decompose a complex problem into understandable components
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Ghulam Ishaq Khan Institute – Spring 2012

What is Object Oriented?
Simplicity through self contained objects
Complexity through integration
Interchangeability through framework

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Ghulam