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7/27/2019 OOA-LectureNotes-01 (1)

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Object Oriented Analysis, 300144 1

Object Oriented AnalysisUnit: 300144; Level: 200; Credit Points 10

Unit IntroductionDr. Quang Vinh Nguyen


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General Information

Object Orietend Analysis, 300144 Level 2 10 Credit Points

Assumed Knowledge

300585 System Analysis and Design

or 300131 Introduction to Analysis and Design or Equivalent Have gained sufficient equivalent knowledge from the prerequisites to

understand and master the concepts discussed and presented in thisOOA unit.

Have a general understanding of what an information system is and

how information system development is undertaken. Comfortable in learning use of the modelling tools and report with

some tutorial assistance such a Visio , Rationals ROSE, orTelelogics TauUML and Word and MS Project


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StaffsDr Quang Vinh Nguyen

Unit Coordinator and Lecturer

Phone: 4736 0482

Email: [email protected] (preferred contact method)

Room: Room Y-353, Bld Y, Penrith campus,

Room , Hot Office, Parramatta campusConsultation hours: Wednesday 11:0012:00 (Parramatta campus)

Monday 11:0012:00 (Penrith campus)

Friday 10:0011:00 (Penrith campus)

Contact Details of the Tutors are available on vUWS


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StaffsMahmoud Elkhodr

Lecturer and Tutor

Email: [email protected] (preferred contact method)

Room: Room UG-25, Bld U, Penrith campus,

Consultation hours: TBA
mailto:[email protected]:[email protected]


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What will be Covered in this Unit The concepts of Object Orientation including the fundamentals, processes and application of the concepts

to practical modelling,

Three modelling spaces: Problem, Solution and Background; Roles in Requirement Analysis,

OO Analysis Techniques, as well as generic techniques such as Interviews, Workshops,

Critical Requirement Analysis and Business Evaluation to arrive at high-level requirements and theirprioritisation,

Package diagrams and high-level slicing of packages as sub-systems,

Quality Software & Business processes. Introduction and documenting Actors and Use Cases,

Introduction to Use Case Diagrams, Use case Notations, Relationships, Analysis & Testing,

Activity diagrams as mechanisms to document the flow of the system/use case

Class Notations and definition of a class including attributes and operations,

Documenting Class Diagram and Relationships between various classes such as Association andInheritance,

Documenting Sequence Diagrams and the persistence design with Class and Sequence Diagrams

Major Ingredients and Creation of State Chart Diagrams, Prototypes and Operational (Non-Functional) Requirements including Performance, Scalability, Security

& Volume,

Quality assurance, management and testing aspects of a system,

Emerging technologies and design


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How the Unit Run

4 Hours per week: two hour lecture (not compulsory but strongly recommended forupdate announcement, latest materials, and workbook exercises)

two hour practical (mandatory)

At least 6 hours self-study (on average)

Lecture sessions scheduled for 12 weeks

no lecture at Mid-Term Test at Week 8

Practical sessions

scheduled for 11 weeks (only 10 marked tutorial sessions)

no practical sessions in first week

Check Student Learning Guide for Further Detail


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Assessment Tutorial/Practical Exercises: 15% (Weekly performance

and attendance) Attendance and doing exercises in tutorials are mandatory

There are 10 group-works (and/or exercises) for markingcorresponding to 10 tutorial sessions.

Attendance and tutorial performance are marked at the last 30 minutesat each tutorial session.

Mid-term Test: 15%, 90 mins test including reading time(Closed book) is held in Week 8 or as specified in class,

Group Assignment (also known as Project Work): 20%, OOAnalysis Model in a CASE tool + Deliverables Report Submission at the last week of the semester or as specified in class

Students attend < 5 tutorials will receive 0 Score for the assignment.

Final Examination: 50%, 120 mins exam including readingtime of 10 mins (Closed book). Must obtain at least 40% in the final examination, and at least 50% as

a total value of all your assessment scores to pass the unit


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Textbook and References

Textbook: Unhelkar, B., Practical Object Oriented Analysis, 2005, Thomson Publishing;ISBN: 0170122980

References: Unhelkar, B., Practical Object Oriented Design, 2005, Thomson Publishing; ISBN:

0170122999. The alternative book that discuss about the design perspectives.

Fowler, M., UML Distilled, 3rd Edition, 2004, Addison-Wesley. ISBN: 0321193687. This isa good readable book and should be referred to in addition to the course material.

Unhelkar, B., Process Quality Assurance for UML-based Projects, 2003, Boston : Addison-Wesley . ISBN: 0201758210. This book contains detailed discussion on the process aspect ofquality. Chapter 1 for UML-based models, Chapter 3 for relevant process components, andChapter 6 for testing are quite relevant.

Booch, G., et al, The UML User Guide, 2005, 2nd edition, Addison-Wesley, ISBN:

0321267974. This is a substantial text and should be occasionally referred to, when students(especially teams) are looking for additional and in-depth material on a particular topic.

Brown, D., An Introduction to Object-Oriented Analysis: Objects and UML in Plain English,2nd edition, 2002, New York: Wiley, ISBN: 0471371378. This book is a very general andaccessible introduction to Object Oriented Analysis. It contains extensive pedagogy andincorporates patient explanations, making it ideal for beginners as a complement readingmaterial.


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Textbook and References (cont) References (cont):

Ian, G., O'Callaghan, A. and Wills, A. C., Object-Oriented Methods: Principles & Practice,3rd edition, Addison-Wesley, 2001, ISBN: 020161913X. This book is very comprehensiveand informative about Object Orientation. This is suitable for deep study students.

George, J.F., Object-Oriented Systems Analysis and Design, 2nd editition, 2007, PearsonPrentice Hall, ISBN: 0132279002. This covers a variety topics in both OO analysis anddesign

Garzas, J. and Piattini, M., Object-Oriented Design Knowledge: Principles, Heuristics, andBest Practices, 2007, Hershey, PA : Idea Group Pub, ISBN: 1591408962. This book issuitable for students who would like to learn more about the design perspective of OO.

Weisfeld, M. A., The object-oriented thought process, 2009, Upper Saddle River, NJ:Addison-Wesley, ISBN: 9780672330162. This book covers the foundation in object-orientedconcepts and then explains how various object technologies are used.

O'Docherty, M., Object-Oriented Analysis and Design: Understanding System Development

with UML 2.0, 2005, Hoboken, NJ : Wiley, ISBN: 0470092408. This book provides athorough grounding in object-oriented analysis and design, providing authoritative andaccessible coverage of object-oriented concepts, the software development process, UMLand multi-tier technologies.

Booch, G. et al., Object-Oriented Analysis and Design with Applications, 2007, Addison-Wesley, ISBN: 020189551X. This book outlines object-oriented methods using the UnifiedModeling Language 2.0 with real applications.


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Textbook and References (cont)

E-Book References (for further deep study) Dennis, A. (2005). Systems analysis and design with UML version 2.0an object-oriented approach (2nd ed.). Hoboken, NJ: Wiley.

Douglass, B. P. (2007). Real time UML workshop for embeddedsystems. Burlington, Mass.: Elsevier.

Larman, C. (2005). Applying UML and patterns: An introduction toobject-oriented analysis and design and iterative development (3rded.). Upper Saddle River, N.J.: Prentice Hall Professional TechnicalReference.

ODocherty, M. (2005). Object-oriented analysis and design:Understanding system development with UML 2.0. Hoboken, NJ:

Wiley. Samek, M. (2009). Practical UML statecharts in C/C++ event-driven

programming for embedded systems (2nd ed.). Amsterdam; BostonNewnes/Elsevier.

Check the Unit page at vUWS for more update resources


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O-O-A

Chapter 1

Fundamentals of Object

Orientation


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Module Outline

Positioning Object Oriented Analysis

Fundamentals of ObjectOrientation

1. Classification

2. Encapsulation

3. Abstraction

4. Inheritance

5. Polymorphism The need of Modeling

Unified modeling language

Mapping the UML to the Modeling Spaces


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What is Object-Oriented?

Encompasses various aspects of softwareDevelopment

Analysis; Design; Implementation; Testing; Metrics;Databases; Architecture - especially Distributed;Management;

Unlike Relational (set) Theory, has noMathematical background; hence noPrecise Definition;


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Some Possible Definitions

A good software engineering practice that

attempts to address new IT challenges

A good approach to build complex and rapidlychanging software applications in the new

millennium - Therefore, may apply to any

software Development

Require a different way of thinking aboutdecomposition, and it produces software architectures

that are largely outside the realm of the structured

design culture


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Software is inherently complex

The complexity of the problem domain

Raw functionality, nonfunctional requirements, e.g.

usability, performance, cost, reliability, security, etc. Communication gap between the users and the

developers

Changes during the development

Whats else? The difficulty of managing the development

process


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Software is inherently complex (cont)

The difficulty of managing the development

process

How much line codes do we normally have for aprogram?

Your program? < 100 lines

First MS DOS Operating System? 100 kbs

Windows XP Operating System? hundreds of Mbs Windows 7 ? Gbytes

modern software can have millions of line codes

and/or hundreds of modules and components


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The flexibility possible through software

Software is required to have high flexibility

The problems of characterising the behaviour ofdiscrete systems

Difficult to know exactly the behaviour with a system

with hundreds or even thousands of variables

Software is inherently complex (cont)


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Why Object-Oriented

OO Software Engineering results in easier

maintainability and extensibility Due to Localized and controlled changes

OO Software Engineering results in more

Opportunities for Reuse Code, Design (including Patterns and Frameworks),

Requirements (Use cases), Components (Link time and Runtime)

The key benefit of OO approach is: hierarchically

breaking down a complex system into manageable

components


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Why Object-Oriented Analysis

OOA is now well beyond the experimental stage and

OOA has entered the mainstream of information

systems development

Accelerated by

The success and rapid spread of object-oriented

programming

Recognition that object-oriented methods produce more

effective, efficient, flexible and stable information systems


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Flowcharts;

SSADM

Entity-Relationships;

Data Flows;

Booch etc. to UnifiedModeling Language

Account Customer

197

0s

19

80s

19

90s

2

000s

Positioning Objects within the

Evolving Technical Thinking


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Programming Language History

Procedure Programming Languages OO Programming LanguagesHigher Languages

Web-Services

Mathematical

Expressions


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Dr. Quang Vinh Nguyen School of Computing and Maths 22

Object-Oriented (O-O)

Programming

Assembly

Statement

ControlLoop

Jump

Program

Procedure

Program

Function

Code

Code

Function

Code

Code

Function

Code

Code

Function

Code

Code

Class

Function

Function

Program

Class

Function

Function

Class

Function

Function

Class

Function

Function

Object-Oriented

Class

Component

Class

Class

Component

Class

Class

Component

Class

Class

Component

Class

Class

Program

Business-Oriented?

Component-Oriented

Code


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Positioning Objects

In 1970s Flowchart and Structured System

Analysis and Design Methods

In 1980s Chens popular Entity Relationshipand Data Flow diagrams

Early 1990s Unified Modeling Language by

Booch.


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Object Orientation; Basis for WebServices and Globalisation

Object-

Orientation

(Components)

Distributed

Computing

Global information systems+

+Web-Services Based

Internet

Technologies

Global Business

Global IT Management


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Learning and Adopting Object

Orientation

Fundamentals ProcessAdopting

OO

Modeling

(UML Standard)

Experience


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Sub-Module

Fundamentals of ObjectOrientation

Basic Concepts


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Classes and Objects

A CLOCK in generalis a CLASS.

YourCLOCK and

My CLOCK are specific

Objects


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What is a Class?

A Class is aDEFINITION, a TEMPLATE, for

the Objects

NOTE:A Class is NOT a Collection ofObjects;

A class is not an individual object, but it

represents a whole set of objects.


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What is an Object?

AnEntity with crisply defined boundaries

Aphysicalorconceptualthing in theproblem and the solution domain

Identity is a unique identifier of an object Has attributes that describe the object, and

also describe thestate in which it exists

Has behaviorthat is manifested in changesto thestate of the object

Sends and receives messages


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What is an Object? (cont)List the attributes and behaviours of the Human Object?


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Objects vs Classes ?

Class: Car

Object 1

Object 2

Object 6

Object 5

Object 4

Object 3Object 7

A class represents a set of objects that share a common structure and a common behaviour

An object is simply an instance of a class


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OO v/s Non-OO (Similarities and

Differences) Non-Object-oriented (Traditional)

Data and Procedures are kept Separate

Procedures work on Data to produce results

Data

ProceduresData

Subprograms


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OO v/s Non-OO (Similarities and

Differences) Object-oriented

Focus on Responsibilities - to be satisfied by Objects

Responsibilities translate into Data and Functions withinan Object

Procedures

Data


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Comparing the Mindsets(Henderson-Sellers, Book of OO Knowledge, Prentice-Hall)

Procedural Mindset

What is the systemsupposed to do?

What are the functionsof the system?

How do I design andcode to achieve the

functions? Focus is on the

algorithms.

OO Mindset

What is the systemmade up of? Objects

What are theresponsibilities ofthese objects?

How will these objects

collaborate to satisfythe responsibilities?

Algorithms/codedeferred


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The Star of OO Fundamentals

CLASSIFICATION

Fundamentals of

Object-Orientation:

THE OBJECT


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Classification

Lithops Lesliei


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Classification

Starting point of object orientation

Grouping meaningful objects.

Classification is based on the requirementsappearing in the problem space.


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Abstraction: 1st Level is from Objects to

Class

FROG

HAT

CLOCK

CAT

Note that these areABSTRACTIONSand

not real Objects. Objects are Classified

and good Classification leads to creation

of good Abstractions. Classes that

represent a collection of Objects are

Abstract.


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Abstraction: 2nd Level is from Classes to

ClassesFROG

ANIMAL

THING

CAT

CLOCK

HAT

Can be Abstracted to

Can be Abstracted to

Classes are abstracted to higher level class


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Classification & Abstraction

Requirements from Problem Space

Can be Classified & Abstracted to

Arrive at Good Classes

MAN

BOOK

CHEST

SHOE

HAT


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Abstraction (and Classification) (cont)

Starts by grouping a given set of (reality) Objectsbased on certain characteristics

Example: Marker Pens, Ballpoint Pens etc.

From the classification (grouping), most commonproperties and behavior is abstractedto arrive at a

Class definition

Infinite number of objects can then be created

(instantiated) from this Class


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Identifying more general groupings to

create Inheritance Hierarchy

BIRD ANIMAL

CRANE

BIRD and ANIMAL

are types ofLIVING thingsLIVING

FROG CAT

MITHU? (my Bird)

PUSPUS? (your Cat)

Are Objects; They

Dont appear on Class

diagrams


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Inheritance

Inheritance in OO is the ability of a Class to

inherit allattributes and behavior of a

higher-level class Classifying with optimum granularity also

leads to good inheritance structure


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Inheritance (cont)

Childclass inherits fromparentclass

Child class shares the attributes and

routines of parent class,plus perhaps addsadditional features

Child class can change implementation ofparent class features

multiple inheritance is permitted; someresolution for name clashes is required


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Moving on the Inheritance Tree

Finding SuperclassesNeeds abstractthinking

Domain knowledge helpful

EssentiallyFOR Reuse

Finding SubclassesConcrete lower level

implementation thinkingEssentially WITH Reuse

Generalization

Specialization

Encapsulation


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Encapsulation

DATA

(Attributes

with States)

METHODS

Encapsulation means

DATA is accessed onlyby METHODS

BEGINPUBLICVISIBILITY

CODE

END

PRIVATEINFORMATION


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Modularity (and Encapsulation) (cont)

When attributes of an Object are NOT

accessed directly by any other Object within

the system but only through the publicinterface of the Object, it is Encapsulation

Objects are modularized to handle complexity,

and encapsulation enhances the advantages by

localizingchanges to within the objects


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Polymorphism

FROG

(move)HORSE

(move)

ANIMAL

(move)

CAT

(move)

(move)

On Receipt of Messagemovefrom a CallingObject, the appropriatemove - depending on whether

it is a Frog or a Horse - will be

executed

Advantage? CALLING object need not know what is Moved, so, if

a new CAT object is added, the CALLING class doesnt change


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Polymorphism..

Essentially the ability of an Entity to behave

differently - even after receiving the same

message Translates to the ability of the software to

substitute different Objects at runtime

Implemented via Inheritance in Object-orientation


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Sub-Module

The Need of ModellingSoftware Development Layers


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MODEL

UnderstandReality

CreateReality

REALITY

Purpose of Modelling: Understand and

Create Reality

(based on Unhelkar, B., 1999, 2003)

M d lli d C l S f


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Modelling and Conceptual Software

Development Layers

(Place of UML)

Languages, Databases

QualityEnvironment

Modeling

Methodologies

Technology

Communication

Management;

Processes

Overall

Management

UML onlydeals

with Modeling.

It is NOTa

Methodology

(or a Process)


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Software Development Layers and

Corresponding CASE TOOL Layer

Java, C++, XML, Oracle etc.

RUP, OPEN, MeNtOR

TauG2; ROSE, Visio.

QSP; ProcessContinuum; Bpwin etc.


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OO Models have a Small Semantic Gap

(fromUnhelkar, CRC Press, 1999)

SEMANTIC GAP

Class:: Passenger Class:: Flight Class:: Seat

Passenger SeatFlight

ANA

LYSIS

DESIGN


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OO facilitates Seamless Transition from Problem to Solution Space

(fromUnhelkar, CRC Press, 1999)

Analysis

(MOPS)

Design

(MOSS)

Implementation

(MOSS)

Class Passenger Class Flight Class Seat

ClassBooking

ClassPriority


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Sub-Module

Modeling SpacesAnd Relating them to the UML

Modelling Spaces and Roles in Analysis, Design


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g p y gand Architecture(A rough role-based guideline)

Model Of Problem

Space (MOPS)

Model Of Solution

Space (MOSS)

Model Of BackgroundSpace (MOBS)

User

BusinessAnalyst

SystemDesigner

Architect

ProjectManager

QualityManager

Understand Problem with Analysis

Create Solut ion with Design ARCHITECT:

App ly Constraints

With Arc hi tecture


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Next Lecture

About the UML Origins and Evolution of the UML

Evolution of the UML

The UML Today Visualizing, Specifying, Construction and Documenting

Some UML based projects

Introduction to UML 2.0

UML 2.0 diagrams and purpose


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Workbook

ExercisesFor Classroom


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Workbook Exercises

1. What is object orientation? What does itencompass?

2. How is object orientation different from procedural

approach to software development?

3. What are the four major factors in learning and

adopting object orientation?

4. List FIVE objects from your current surroundings.

5. Create at least TWO classes from the above fiveobjects (This will help you understand the difference

between a class and an object).


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Workbook Exercises

6. List next to each of the above TWO classes, at leastFIVE attributes.

7. Discuss the importance of each of the fundamentalsof OO within the context of software engineering.

8. What is a process and how it is different frommodeling?

9. What are the two main reasons for creating models?

10. How is object-oriented modeling advantageous?

11. Name the three modeling spaces in OO modeling.Discuss the advantage of modeling in each of thesethree modeling spaces.


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Conclusions Software Development benefits with Process and

Modeling; UML is OMGs standard for Modeling;

OO has Five Fundamentals

Classification; Abstraction; Inheritance;Encapsulation and Polymorphism

Class is a Template; Object is an Instance;

All Modeling Work happens in 3 Spaces:

MOPS; MOSS; and MOBS

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