modeling structure – class diagram. class diagram

Modeling Structure – Class Diagram

Class Diagram

Operations (behaviors) to fulfill the class’s responsibilities.

Object class name

Attributes

Steps in Developing a Class Diagram

Identify object classesIdentify associationsIdentify object attributesOrganize object classes using inheritanceDescribe communication using sequence diagramsGroup classes

Class

attributes

subClass

subClass

operations

Class Diagram

Object

Object

Object

subClass

Relationships between classes

1. Associations 2. Composition/Aggregation3. Generalization/Specialization

Associations– relationship between classes– E.g, Employee works in Department– Specifies how many instances of one class may

relate to a single instance of another class

• 1-to-1 association • Optional association (0, 1, or many) – Company has President – Customer owns Credit

Card• 1-to-many association • Many-to-Many

association – Bank manages Account – Course has Student

– Student attends Course

Showing Association                                                   

An Association between two classes is shown by a simple line. It can be given a descriptive name and augmented with the Role played by each class and with the Cardinality of the relationship.

Associations

Has-capital

One-to-one association

One-to-many association

City

name:String

Workorder

schedule()

StickyNote

x: Integery: Integerz: Integer

*

Country

name:String

[From Bruegge, 2000]

Many-to-Many Associations

Work on **Mechanics Plane

[From Bruegge, 2000]

Sample UML Cardinality Notations

Multiplicity Multiplicity

Works for

0..1Has

0..*Makes

UML

Notation Association with Multiplicity Association

Meaning

Exactly 1

1

or

leave blank

DepartmentEmployee1Works for

DepartmentEmployee

An employee works for one and only one department.

Zero or one 0..1 SpouseEmployeeAn employee has either one or no

spouse.

Zero or more

0..*

or

*

PaymentCustomer

PaymentCustomerMakes *

A customer can make no payment

up to many payments.

One or more 1..* CourseUniversityOffers 1..* A university

offers at least 1 course up to

many courses.

Specific range 7..9 GameTeam

7..9Has

scheduled A team has either 7, 8, or 9 games

scheduled

Composition and Aggregation Hierarchies• Whole/Part Relationships

– Show components of more complex class– Composition is stronger relationship than aggregation

• Composition Hierarchy– Whole and part objects are created, live, die together– Often also has a physical association– Association between instances

• Aggregation Hierarchy– Part objects of aggregate object may be created and deleted independently of aggregate object– Often used for more abstract whole/part relationships than composite objects

Showing Aggregation                                    

If one class is contained within another a solid diamond is placed on the line next to the containing class. This is termed by value, Class2 it essentially a value within Class1.

If the relationship is a simple aggregation then an empty diamond is used. This is termed by reference, Class1 refers to Class2.

Kereta

RodaEnjin TempatDuduk

Aggregation Example

weight

Automobile

serial numberyearmanufacturermodelcolor

drivepurchase

Aggregation Example

Engine

horsepowervolume

onoff

4,6

Wheel

diameternumber of bolts

2,4

Door

openclose

Battery

ampsvolts

chargedischarge

*

Brakelight

onoff

[From Bruegge, 2000]

• Some classes are similar but not identical – Have some attributes in common, others different

• Common attributes abstracted into generalized class(superclass) – E.g., Account (Account number, Balance)

• Different attributes are properties of specialized class(subclass) – E.g., Savings Account (Interest)

• IS A relationship between subclass and superclass – Savings Account IS A Account

Generalization / Specialization Hierarchy

‘generalization’ showing inheritance 

Inheritance is shown by a line from the sub-class to the super-class with an arrow pointing to the super class.

Super class

Sub class

STAF

NamaAlamatGajiNo.staf

STAFPengeluaran

Kiragajicetakslipgaji

STAFPentadbiran

Kiragajicetakslipgaji

Pengurus

Kiragajicetakslipgaji

Example : Inheritance

UML Representation of Generalization/Specialization

walk()jump()talk()sleep()eat()etc.()

last namefirst namebirthdategender

Person

enroll()displayGPA()

GPAclassification

Student

lecture()

rank

Teacher

Arrowhead indicatesgeneralization/specializationrelationship

Inheritance Example

Cell

MuscleCellBloodCell NerveCell

StriateSmoothRed White PyramidalCortical

[From Bruegge, 2000]

*

Light

offon

1

1

Heater1

Cooler

1

Environmental Controller

Define_climateTerminate_climate

*

1

1

1

1

1

SystemLog

DisplayRecordEvent

Actuator

startUpshutDown

Temperature

Example : Class Diagram

User

AddressMember#NameSubscribeUnsubscribe

External Reader

Ext. Library NameBorrower

Items BorrowedMaximum Loans

Library Item

No. CopiesShelfNoStatusTitleIssueReturnShelve

Book

AuthorISBNPub. DatePublisher

CAL Package

Distributor

Recorded Media

Course Text

Borrows

Aggregation

Association GeneralizationObject /Class

0..*

Example : Class Diagram

Summary – Class Relationship

PlanAnalyst

PlanMetrics

Plan

GrowingPlan GardeningPlan

Controller Cooler

Light Heater

FruitGrowingPlan

Food

Vitamin Calorie

analyzes

1..2

1..*

1..231 1

*

* 1

**

* 1

AGGREGATION

ASSOCIATIONGENERALIZATION/ INHERITANCE

COMPOSITION

<<actor>>Club Member

Member-Date-Of-Last-OrderMember-Daytime-Phone-NumberMember-Credit-Card-Expire-DateMember-Credit-Card-NumberMember-Credit-Card-TypeMember-Balance-DueMember-Bonus-Balance-AvailableAudio-Category-PreferenceAudio-Media-PreferenceDate-EnrolledEmail-AddressGame-Category-PreferenceGame-Media-PreferenceNumber-Of-Credits-EarnedPrivacy-CodeVideo-Category-PreferenceVideo-Media-Preference

persistent

Member Order

Order-NumberOrder-Creation-DateOrder-Fill-DateShipping-Address-NameShipping-Street-AddressShipping-CityShipping-StateShipping-Zip-CodeShipping-InstructionsOrder-Sub-TotalOrder-Sales-TaxOrder-Shipping-MethodOrder-Shipping-&-Handling-CostOrder-StatusOrder-Prepaid-AmountOrder-Prepayment-Method

persistent

Product

Product-NumberUPC-Quantity-In-StockProduct-TypeSuggested-Retail-PriceDefault-Unit-PriceCurrent-Special-Unit-PriceCurrent-Month-Units-SoldCurrent-Year-Units-SoldTotal-Lifetime-Units-Sold

persistent

Video Title

ProducerDirectorVideo-CategoryVideo-Sub-CategoryClosed-CaptionedLanguageRunning-TimeVideo-Media-TypeVideo-EncodingScreen-AspectMPA-Rating-Code

persistent

Audio Tilte

ArtistAudio-CategoryAudio-Sub-CategoryNumber-Of-Units-In-PackageAudio-Media-CodeContent-Advisory-Code

persistent

Transaction

Transaction-Reference-NumberTransaction-DateTransaction-TypeTransaction-DescriptionTransation-Amount

persistent

Member

Member-NumberMember-NameMember-StatusMember-Street-AddressMember-PO-BoxMember-CityMember-StateMember-Zip-Code

persistent

Agreement

Agreement-NumberAgreement-Expire-DateAgreement-Active-DateFulfillment-PeriodRequired-Number-Of-Credits

persistent

Game Title

ManufacturerGame-CategoryGame-Sub-CategoryGame-PlatformGame-Media-TypeNumber-Of-PlayersParent-Advisory-Code

persistent

Title

Title-Of-WorkTitle-CoverCatalog-DescriptionCopyright-DateEntertainment-CompanyCredit-Value

persistent

Member Ordered Product

Quantity-OrderedQuantity-ShippedQuantity-BackorderedPurchase-Unit-PriceCredits-Earned

persistent

Merchandise

Merchandise-NameMerchandise-DescriptionMerchandise-TypeUnit-of-Measure

persistent

Promotion

Promotion-NumberPromotion-Release-DatePromotion-StatusPromotion-Type

persistent

<<actor>>Potential Member

persistent

<<actor>>Past Member

Expiration-Date

persistent

Return

persistent

1..*

1binds

1

0..*

Conducts

1

0..*

Haspurchased

0..10..*

Generates

0..*

1..*

Features

1

0..*

Sold as

0..*

1

Places

1

1..*

Sells

Member Services System Class Diagram

Class Diagram for KMT Client

prepare() prepare()

check()

[check=“true”] remove()

needsToReorder()

[needsToReorder=“true”]

enter new

Reorder Item

Delivery Item

Order Entry window

Order Order Line Stock Item

[check=“true”] enter new

Sequence Diagram

ReOrderItem

itemnumberquantityetc…

DeliveryItem

deliveryadressquantityetc…

Order

orderNumberdateetc…

prepare()

OrderLine

itemnumberquantityetc…

StockItem

orderNumberminQuantitydateetc…

needsToReorder(): boolean

check(): booleanremove()

is_for

prepare()enter new()

enter new()

Computer: Computer

PrintServer:PrintServer

Printer:Printer

print(file)

User: User

print(filename)

Queue:Queue

[printer free] print(file)

[printer busy] store(file)

Computer

print(filename)

PrintServer

status(): integer

print(file)

Printer

print(file)

Queue

store(file)

uses

Managed by

Recap• After studying this chapter we learned

to:– Understand how to structure

requirements with class diagram.

– Explain the element of class diagrams

– Construct class diagrams.