This document discusses object-oriented analysis and design (OOAD). It introduces key OOAD concepts like classes, objects, abstraction, encapsulation, inheritance, polymorphism, and associations. It explains that OOAD implements object-oriented analysis to develop an object model of the problem, object-oriented design to develop a model of the solution, and object-oriented programming to develop the model using an OO language. The document also discusses using the Unified Modeling Language (UML) for OOAD, with examples of use case diagrams and class diagrams. It provides external readings on OOAD and gives homework questions related to analyzing a class diagram for an elevator system.

1. Object-oriented analysis and
design
SENG 123:
Introduction to Computer Software Engineering
By
Atilla Elçi
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2. WEEKLY SCHEDULE
Week Topics PPTs Text
1 Intro to the course;
An overview of software engineering concepts
Intro;
Concepts
Preface;
Ch.1
2 Engineering, software engineering, ethics Engin…
3 Software development life cycle SDLC Ch.2
4 Software development life cycle SDLC Ch.2
5 Practical UML -
6 Requirements analysis and software
specification
Req Ch.3
7 Midterm Examination Week 25.11.2020 18:00-21:00
8 Software development project management PM Ch.4- 1st half
9 Software project analysis and design SAD Ch.5
10 Object-oriented analysis and design OOAD Ch.6- 1st half
11 Interfaces, dialogs, and database
12 coding and debugging; software testing
13 Implementation and maintenance; reliability and
quality
14 Review; Q & A.
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3. Here
we
are!
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4. Object-Oriented Analysis and Design
• Three approaches to A&D:
1. Procedure-(/Function-)oriented
2. Data-oriented
3. Object-oriented: combining both into an ‘object’
• Objects: things an IS deals with, e.g., chairs,
customers, pens, payrol slip, wheather
forecast, …
• An object-oriented system is made up of
interacting objects that maintain their local
state and provide operations on that state.
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5. Object orientation
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• OO approach: Create a set of classes
(including attributes, then expand by
adding capabilities(/behaviours)
• Class versus object:
– Class is a category
– Object is an instance in a category
– Class is used as template to create
objects
• A software model is a collection of
classes (therefore also of behaviors)
• Let’s work out some examples of
classes and objects:
– Person: Berke
– Car: Toyota RAV4, Renault Megane
– …
Name
Attributes
Behaviors

6. OO Paradigm concepts
• Abstraction: essential attributes and behaviors of a class required for the
model
• Encapsulation, info hiding: Inside of an object cannot be seen but can only
be used by calling its behaviors.
• Inheritance: In a hierarchy of classes, a subclass inherits its superclass’s
attributes and behaviors.
• Generalization/Specialization: same as inheritance
• Polymorphism: a behavior name appearing in different classes will mean
different operation as assigned in class definition.
• Messages: objects interwork by sending messages to each other.
• Association: objects are associated (linked) to others by unidirectional,
bidirectional, one-on-one, one-to-many associations
– Let’s study Figures 6.12-18.
• Aggregation/composition: A class may be a collection of other classes.
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7. OOAD Paradigm
• Object-oriented strategy (/paradigm) implements in succession the
following (see Fig. 6.23):
– OO analysis: develops an OO model of the problem
– OO design: develops an OO model of the solution
– OO programming: develops the model using an OO language.
• This strategy reduces SDLC to OODLC (see Fig. 6.24):
– OO analysis
– OO design
– Object implementation
• Essentially all are summarized in using UML!
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8. OOAD: UML Diagrams
• Use Case Diagram: let’s study Figs 6.30 & 31
• Class Diagram: let’s study Fig. 6.32
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9. Readings on OOAD
• OOAD:
– Quick guide:
• https://www.tutorialspoint.com/object_oriented_analy
sis_design/ooad_quick_guide.htm
– Detailed:
• https://www.tutorialspoint.com/object_oriented_analy
sis_design/index.htm
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10. Terminology - Terimler continued
• Object-Oriented Analysis and
Design: Nesne-yönelimli
çözümleme ve tasarım
• OOAD: NYÇT
• X-oriented: X-yönelimli
• Procedure-oriented: süreç-
yönelimli
• Data-oriented: veri-yönelimli
• Object-oriented: nesne-
yönelimli
• Implementation:
gerçekleştirme
• Behavior: davranış
• Function: işlev
• Abstraction: soyutlama
• Encapsulation, info hiding: bilgi
gizleme
• Inheritance: kalıt, miras
• Generalization/Specialization:
genelleştirme/özelleştirme
• Polymorphism: çok biçimlilik
• Message: ileti
• Association: ilişki
• Unidirectional: tek yönlü
• Bidirectional: iki yönlü
• one-on-one: bire bir
• one-to-many: bire çok
• Aggregation/composition:
birleştirme
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11. Homework
• Answer the following Qs in terms of OO Paradigm concepts
reference Figure 6.36: The detailed class diagram of elevator
problem:
– How many classes are there in this class diagram?
– What is the relationship between Button Class and Elevator Button
Class?
– What are Elevator Button Class and Floor Button Class to Button Class?
– What is the cardinality of the relationship between Elevator Button
Class and Elevator Control Class? What about Elevator Doors Class and
Elevator Control Class?
– Both Elevator Button Class and Floor Button Class have turnOffButton
and turnOnButton functions. What OO paradigm concept does that
signify?
– What does the ‘Controls’ indication mean?
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12. These are FYI!
• Microsoft: Turning Excel into a Turing-
complete programming language:
– https://www.techrepublic.com/article/microsoft-
turning-excel-into-a-turing-complete-
programming-language/
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