Visual Modeling Unified Modeling Language( Uml)

8/14/2019 Visual Modeling Unified Modeling Language( Uml)

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Object OrientedObject Oriented

Analysis AndAnalysis And

design Throughdesign ThroughUMLUML


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This sessionThis session

Introduction to modelingIntroduction to modeling Class diagramsClass diagrams

Use case diagramsUse case diagrams

Sequence DiagramsSequence Diagrams


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Introduction to ModelingIntroduction to Modeling

What is a model?What is a model?

A model is a simplification of realty.A model is a simplification of realty.

Why do we model?Why do we model?

We build models so that we can betterWe build models so that we can better

understand the system we are developingunderstand the system we are developing


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How can you realize theHow can you realize the

benefits of modeling?benefits of modeling?


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What is the UMLWhat is the UML

The UML is the standard language forThe UML is the standard language for Visualizing,Visualizing,

Specifying,Specifying,

Constructing, andConstructing, and

DocumentingDocumenting

the artifacts of a software-intensive systemthe artifacts of a software-intensive system


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RELATIONSHIPS

DIAGRAMS

THINGS

STRUCTURAL

BEHAVIORAL

GROUPING

ANNOTATIONAL

DEPENDENCY

ASSOCIATION

GENARALIZATION

REALIZATION

1. CLASS

2. OBJECT

3. COMPONANT

4. USE CASE

5. SEQUENCE

6. COLLOBORATION

7. ACTIVITY

8. AND OTHERS


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All the modeling techniquesAll the modeling techniques

in briefin briefSequence

Diagrams

Collaboration

diagrams

State

MachineDiagrams

Activity

Diagrams

Deployment

Diagrams

ComponentDiagrams

Object

Diagrams

Class

diagrams

Use case

diagrams

UML

MODELS


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Classification of UMLClassification of UML

Structural model viewStructural model view

1) class diagrams1) class diagrams

2) object diagrams2) object diagrams

user model viewuser model view

1) use case diagrams1) use case diagrams

Behavioral model viewBehavioral model view

1) sequence diagrams1) sequence diagrams

2) collaboration diagrams2) collaboration diagrams

3) state machine diagrams3) state machine diagrams

4) activity diagrams4) activity diagrams

Implementation model viewImplementation model view

1)component diagrams1)component diagrams

Environment model viewEnvironment model view

1) deployment diagrams1) deployment diagrams


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Structural modelStructural model

viewviewClass DiagramsClass Diagrams

Object DiagramsObject Diagrams


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DEPENDENCY GENARALIZATIO

REALIZATION ASSOCIATION

Class diagram

Structure &behavior

Relationships Multiplicity &Navigation

ne Class uses the

formation of otherOne class specifiesA contract that other

Class will carru out

Objects of one thing areConnected to objects

Of another

Relationship betweenGeneral kind of class

And a more specificKind of class


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Structure of a ClassStructure of a Class

A class is a collection ofA class is a collection ofobjects with commonobjects with commonstructure, common behavior,structure, common behavior,common relationships andcommon relationships and

common semanticscommon semantics

Classes should be namedClasses should be namedusing the vocabulary of theusing the vocabulary of thedomaindomain Naming standards should beNaming standards should be

createdcreated e.g., all classes aree.g., all classes are singularsingular

nounsnouns starting with a capitalstarting with a capitalletterletter

ClassNameClassName

AttributesAttributes

OperationsOperations

ResponsibilitiResponsibilitieses


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Operations andOperations and

AttributesAttributes

OperationsOperations ::The behavior of a class is represented by itsThe behavior of a class is represented by itsoperationsoperations

AttributesAttributes ::The structure of a class is represented by itsThe structure of a class is represented by itsattributesattributes

ResponsibilitiesResponsibilities:: It is a contract or an obligation of a classIt is a contract or an obligation of a class..


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Advanced RelationshipsAdvanced Relationships

AggregationAggregation:: It is a special kind of association and is used when oneIt is a special kind of association and is used when oneclass (whole) consists of 1 or more smaller classes (parts). It shows has-aclass (whole) consists of 1 or more smaller classes (parts). It shows has-arelationship between the whole and its parts.relationship between the whole and its parts.

CompositionComposition ::This specifies that the lifetime of theThis specifies that the lifetime of thepart classifier is dependent on the lifetime of the wholepart classifier is dependent on the lifetime of the whole

classifierclassifier

InheritanceInheritance ::There are two ways to findThere are two ways to findinheritance:inheritance: GeneralizationGeneralization:: As you move "up" the hierarchy, you achieveAs you move "up" the hierarchy, you achieve

greater generalization . You move up toward Mammal to generalize thatgreater generalization . You move up toward Mammal to generalize thatdogs, cats, and horses all bear live youngdogs, cats, and horses all bear live young.. SpecializationSpecialization:: As you move "down" the hierarchy youAs you move "down" the hierarchy you

specialize. Thus, the cat specializes Mammal in having claws (aspecialize. Thus, the cat specializes Mammal in having claws (acharacteristic) and purring (a behaviorcharacteristic) and purring (a behavior


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Multiplicity and NavigationMultiplicity and Navigation

MultiplicityMultiplicity defines how manydefines how manyobjects participate in a relationshipobjects participate in a relationship Multiplicity is the number ofMultiplicity is the number of

instances of one class related toinstances of one class related toONE instance of the other classONE instance of the other class

For each association andFor each association andaggregation, there are twoaggregation, there are two

multiplicity decisions to make:multiplicity decisions to make:one for each end of theone for each end of therelationshiprelationship

IfIfnavigationnavigation is restricted, anis restricted, anarrowhead is added to indicate thearrowhead is added to indicate thedirection of the navigationdirection of the navigation

IndicatoIndicatorr

MeaningMeaning

0..10..1 Zero or oneZero or one

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One onlyOne only

0..*0..* Zero or moreZero or more

1..*1..* One or moreOne or more

nn OnlyOnly nn ((nn > 1)> 1)

0..n0..n Zero toZero to nn ((nn> 1)> 1)

1..n1..n One toOne to nn ((nn > 1)> 1)


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A small Work outA small Work out

Try to make Class diagram for aTry to make Class diagram for abanking system ?????????banking system ?????????

NOWNOW


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Building a systemBuilding a system


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user model viewuser model view

Use case DiagramsUse case Diagrams


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RelationshipsBetween Actors

& usecases

Use CaseDiagrams

Behavior orUSE CASEActor

What's up inWhat's up in

usecases??????usecases??????

An actor is aAn actor is aperson,person,

organization,organization,

or externalor external

system thatsystem that

plays a role inplays a role in

one or moreone or more

interactionsinteractionswith yourwith your

I t d ti t USE CASEI t d ti t USE CASE


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Introduction to USE CASEIntroduction to USE CASE

diagramsdiagrams

What is a use case diagram??What is a use case diagram??AA use case diagramuse case diagram is a type ofis a type ofbehavioral diagrambehavioral diagram. whose purpose is to. whose purpose is to

present a graphical overview of the functionality provided by a system in termspresent a graphical overview of the functionality provided by a system in termsof actors, their goals (represented as use cases), and any dependenciesof actors, their goals (represented as use cases), and any dependencies

between those use casesbetween those use cases

What do they represent?What do they represent?

They represent the functionality of the system from users point of viewThey represent the functionality of the system from users point of view

who will be using the system?who will be using the system?

ACTORACTOR

what will they be using it to do? ?what will they be using it to do? ?

USECASEUSECASE


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Who is an actor???Who is an actor???

For example, a bank cardholder might need to use an ATM to getFor example, a bank cardholder might need to use an ATM to getcash out of their account. It is as simple as that.cash out of their account. It is as simple as that. Actors don't have to be people. They can be other systems. ForActors don't have to be people. They can be other systems. For

example, the ATM may need to connect to the cardholder's bank.example, the ATM may need to connect to the cardholder's bank.External systems that interact in a use case are also actors.External systems that interact in a use case are also actors.

actor system goal


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What Is A Use Case Scenario?What Is A Use Case Scenario?

Some examples ofSome examples ofuse case scenariosuse case scenarios.. When a cardholder tries to withdraw cash from an ATM, itWhen a cardholder tries to withdraw cash from an ATM, it

doesn't always necessarily turn out the same way.doesn't always necessarily turn out the same way. Sometimes he gets his money.Sometimes he gets his money. Other times he might have insufficient funds.Other times he might have insufficient funds.

Or the ATM may be out of cashOr the ATM may be out of cash

The outcome is different, depending on circumstances, but theyThe outcome is different, depending on circumstances, but theyall relate to the same functional goal . that is, they're all triggeredall relate to the same functional goal . that is, they're all triggeredby the same need and all have the same starting point.by the same need and all have the same starting point.


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Capturing Use Case Scenarios withCapturing Use Case Scenarios with

Essential Use Case DescriptionsEssential Use Case Descriptions Dont go into technical aspect ofDont go into technical aspect of

the designthe design We first need toWe first need to understand what theunderstand what the

business logicbusiness logic of the interactions are,of the interactions are,so we can focus on satisfying theso we can focus on satisfying thebusiness goal of the use case.business goal of the use case.

Instead of saying the user presses theInstead of saying the user presses theenter button, we say the userenter button, we say the userconfirms their choice, for example.confirms their choice, for example.

split the actions into columns, onesplit the actions into columns, onefor each actor and one for thefor each actor and one for thesystem. Then we can see at asystem. Then we can see at aglance not only the order of eventsglance not only the order of eventsin a use case scenario, but alsoin a use case scenario, but alsoexactly who is doing what.exactly who is doing what.

AnAn essential use caseessential use case clearly showsclearly showsthethe order of eventsorder of events and theand theresponsibilities of the actor(sresponsibilities of the actor(s) and) andsystemsystem in a single use case scenario,in a single use case scenario,without committing to technicalwithout committing to technicaldesigndesign decisionsdecisions

select withdrawal optiondisplay withdrawaldisplay withdrawaloptionsoptions

specify amountspecify amountcheck card holdercheck card holder

hashasSufficient fundsSufficient funds

eject cardeject card

prompt cardholder to takeprompt cardholder to take

cardcard

take cardtake carddispense amountdispense amount

prompt cardholder to takeprompt cardholder to takecashcashtake cashtake cashdebit cardholdersdebit cardholders

accountaccountthank cardholderthank cardholder

display welcome and awaidisplay welcome and awainext holdernext holder


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Usecase1

Usecase2

actor

Depiction of actor and usecase


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Remember that use case designs aren'tRemember that use case designs aren't

the same thing as requirements. Thesethe same thing as requirements. These

are high-level interaction designs. ifare high-level interaction designs. if

we mix them up with real requirementswe mix them up with real requirements

stuff the system really has to do ,thenstuff the system really has to do ,then

we can get bogged down in the designwe can get bogged down in the design

decisions we make early on.decisions we make early on.

WARNINGWARNING


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Documenting Use CasesDocumenting Use Cases

A flow of events document is created for eachA flow of events document is created for eachuse cases Written from an actor point of viewuse cases Written from an actor point of view

Details what the system must provide to theDetails what the system must provide to theactor when the use cases is executedactor when the use cases is executed

Typical contentsTypical contents How the use case starts and endsHow the use case starts and ends

Normal flow of eventsNormal flow of events

Alternate flow of eventsAlternate flow of events

Exceptional flow of eventsExceptional flow of events

e at ons ps etween


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e at ons ps etweenUse Cases

Including Use Cases: Whentwo or more use casesinclude the flow of anotheruse case, they are said toinclude that use case's flow.

Extending Use Cases: relationship

means that the flow of theextending use case is onlyincluded under specificconditions

Check tutor availa

Book assesment

Book lesson

View Product

Review Product

Check Login


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Summary of use casesSummary of use cases

1. Identify your actors: who will be using the system?2. Identify their goals: what will they be using the system to do?

3. Identify key scenarios: in trying to achieve a specific goal, whatdistinct outcomes or workflows might we need to consider?

4. Describe in business terms the interactions between the actor(s)and the system for a specific scenario

5. Create a UI prototype that clearly communicates the scenario totechnical and

6. non-technical stakeholders

7. Do a high-level OO design for the scenario8. Implement the design in code9. Get feedback from your users . ideally through structured

acceptance testing10. Move on to the next scenario or use case (.rinse and repeat.)


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Try to make Use case diagram for aTry to make Use case diagram for abanking system ?????????banking system ?????????

NOWNOW


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Behavioral ModelBehavioral Model

ViewView1.1. Sequence DiagramsSequence Diagrams

2.2. Collaboration DiagramsCollaboration Diagrams

3.3. State Machine DiagramsState Machine Diagrams4.4. Activity DiagramsActivity Diagrams


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Sequence DiagramsSequence Diagrams

The sequence diagram is used primarily toThe sequence diagram is used primarily to

show the interactions between objects in theshow the interactions between objects in the

sequential order that those interactions occur.sequential order that those interactions occur.

useful to communicate how the businessuseful to communicate how the businesscurrently works by showing how variouscurrently works by showing how various

business objects interact.business objects interact.

business-level sequence diagram can be usedbusiness-level sequence diagram can be used

as a requirements document to communicateas a requirements document to communicaterequirements for a future systemrequirements for a future system

implementation.implementation.


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Notation BasicsNotation Basics

Lifelines:Lifelines: Lifelines are drawn as a box with a dashed line descending from theLifelines are drawn as a box with a dashed line descending from thecenter of the bottom edge .The lifeline's name is placed inside the box.center of the bottom edge .The lifeline's name is placed inside the box.

Messages:Messages: The first message of a sequence diagram always starts at the topThe first message of a sequence diagram always starts at the topand is typically located on the left side of the diagram for readability. Subsequentand is typically located on the left side of the diagram for readability. Subsequent

messages are then added to the diagram slightly lower then the previous message.messages are then added to the diagram slightly lower then the previous message.

Guards:Guards: Guards are used throughout UML diagrams to control flow.Guards are used throughout UML diagrams to control flow.WhenWhenmodeling object interactions, there will be times when a condition must be met for amodeling object interactions, there will be times when a condition must be met for a

message to be sent to the object.message to be sent to the object.

Alternatives :Alternatives : Alternatives are used to designate a mutually exclusiveAlternatives are used to designate a mutually exclusivechoice between two or more message sequences. Alternatives allow the modeling ofchoice between two or more message sequences. Alternatives allow the modeling of

the classic "if then else" logicthe classic "if then else" logic


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Life lines

Messages

Guards


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Alternative


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Try to make Sequence diagram for aTry to make Sequence diagram for abanking system ?????????banking system ?????????

NOWNOW

Visual Modeling Unified Modeling Language( Uml)

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