Seminar 2 : The state of the practice

Programming Paradigms

[The Paradigms - Group 2]

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Most of us will be in I.T Industry

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Being experts in a paradigm can help us climb up the corporate ladder

Architect

Designer

Programmer

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Object-Oriented Paradigm

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Everyone knows how to use Object-Oriented Programming Languages

JAVAC++C# JAVASCRIPT

PHP

Objective-c

Python

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But does knowing

OO programming languages equivalent to knowing

OO paradigm?

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Let us be Experts in OO Paradigm And overcome its limitations

Training : OO Characteristics

Skill 1: OO Analysis

Skill 2: OO Design

Skill 3: Overcoming Limitations

Quest: Mastery of OO

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Recap: What is OO Paradigm?

Characteristics of OO

Training : OO Characteristics

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Let’s Recap:What is Object-Oriented Paradigm?

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Recap

Object-Oriented Paradigm

View everything as objects which– Behaviors– Properties

Name:Gender:Size:Eye _colour:Shopping()

Human

Animal

“Alice”

“Bob”

Building

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Abstraction

Encapsulation

Inheritance

PolymorphismCharacteristics of OO

But have you misunderstood any of

these concepts?

OO Characteristics? You know that…

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Scenario: Looking for an item in Challenger

Weak OO Model

14Straight OO Modeling

Weak OO Model

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Recap: What is OO Paradigm?

Characteristics of OO

Training : OO Characteristics

Abstraction Encapsulation Inheritance Polymorphism

Abstraction: A high level view

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

Eliminate the Irrelevant, Amplify the Essential

The Vet Point of View

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

• Relevant•Parts of the cat•Etc…

• Irrelevant•Favorite Toy•Etc…

The Owner Point of View

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

• Relevant•Favorite Toy•Etc…

• Irrelevant•Scientific Names of the cat’s body parts•Etc…

Programming Point of View

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

US Keyboard

getAlphabet()getNumeric()getFunction()

ATM Keyboard

getNumeric()getFunction()

Encapsulation

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

Hiding the Unnecessary

Programming Point of View

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

Student+ StudentID+ CAP

Student- StudentID- CAP

Private Public

Programming Point of View

Main Concepts of OOAbstraction Encapsulation Inheritance Polymorphism

Student+ StudentID+ CAP

Public

•Drawbacks• Bypass checking• Breach integrity• Break in code when

there is change • Vulnerable to malicious

attack

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Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

They might look the similar, but they are not.

Father SonModeling the Similarity

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

StudentnamegenderaddressphoneNumbermatricNo

driveVehicle()

ProfessornamegenderaddressphoneNumberstaffID

driveVehicle()

What if we have bugs in the algorithm of driveVehicle()?

Programming Point of View

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

StudentnamegenderaddressphoneNumbermatrixNo

driveVehicle()

ProfessornamegenderaddressphoneNumberstaffID

driveVehicle()

A Better Solution

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

Personnamegenderaddress

driveVehicle()

Base Class

StudentmatricNo

…

ProfessorstaffID

…

Derived Class

(Generalization)

(Specialization)

Inheritance is used to express “is a” relationship.

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Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

If you ask different animal to “speak”, they responds in their own way.

Same Function Different Behavior

Characteristics of OO

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Abstraction Encapsulation Inheritance Polymorphism

computeSalary()

accountant.computeSalary() CEO. computeSalary() programmer. computeSalary()

computeSalary() computeSalary()

Programming Point of View

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Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

Polymorphism treats each instance of different classes the same way within a system.

Employee.computeSalary()

computeSalary() computeSalary() computeSalary()

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

We can use Inheritance to apply polymorphism.

Employee

computeSalary ()

computeSalary() computeSalary() computeSalary()

Employee object = new CEO();

object.computeSalary();

Characteristics of OOAbstraction Encapsulation Inheritance Polymorphism

computeSalary() computeSalary() computeSalary()

Polymorphism reduce development effort with the help of dynamic binding property.

//people is a list that contains some Accountant, CEO and Programmer objects.

for (Employee p :people){ p.computeSalary();}

Employee

computeSalary ()

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OO CharacteristicsAbstraction“Eliminate the Irrelevant,

Amplify the Essential”

Encapsulation“Hiding the Unnecessary”

Inheritance“Modeling the Similarity”

Polymorphism“Same Function Different Behavior”

Strong OO ModelReinforce weak OO model with 4 characteristics.

Strong OO ModelAbstraction

• Abstract only relevant information for Multimedia Class

Strong OO ModelEncapsulation

• Protect attributes from any direct access

Strong OO ModelInheritance

• Extend Multimedia class to more than one class with specialized functionalities

Strong OO ModelPolymorphism

• Apply polymorphism for common method with different implementation

Training : OO Characteristics

Skill 1: OO Analysis

Skill 2: OO Design

Skill 3: Overcoming Limitations

Quest: Mastery of OO

Thank you!

End of Presentation