Introduction to UMLIntroduction to UML

Mohammad Zubair AhmadMohammad Zubair Ahmad

Spring, 2007Spring, 2007

AcknowledgementsAcknowledgements

►Most of the lecture slides were Most of the lecture slides were adopted from the slides of Mr. Shiyuan adopted from the slides of Mr. Shiyuan Jin’s UML class, EEL 5881, Fall 2003.Jin’s UML class, EEL 5881, Fall 2003.

OverviewOverview

► What is UML?What is UML?► A brief history of UML and its origins.A brief history of UML and its origins.► Understanding the basics of UML.Understanding the basics of UML.► UML diagrams UML diagrams ► UML Modeling toolsUML Modeling tools

What is UML?What is UML? ► The Unified Modeling Language (UML) is a The Unified Modeling Language (UML) is a

industry-standard graphical language for industry-standard graphical language for specifying, visualizing, constructing, and specifying, visualizing, constructing, and documenting the artifacts of software systems, documenting the artifacts of software systems, as well as for business modeling.as well as for business modeling.

► The UML uses mostly graphical notations to The UML uses mostly graphical notations to express the OO analysis and design of software express the OO analysis and design of software projects.  projects. 

► Simplifies the complex process of software Simplifies the complex process of software designdesign

Why UML for ModelingWhy UML for Modeling

► Use graphical notation to communicate more Use graphical notation to communicate more clearly than natural language (imprecise) and clearly than natural language (imprecise) and code(too detailed).code(too detailed).

► Help acquire an overall view of a system.Help acquire an overall view of a system.

► UML is UML is not not dependent on any one language or dependent on any one language or technology.technology.

► UML moves us from fragmentationUML moves us from fragmentation to to standardizationstandardization..

HistoryHistory

Time

1997: UML 1.0, 1.1

1996: UML 0.9 & 0.91

1995: Unified Method 0.8

Other methods

Booch ‘91

Booch ‘93 OMT - 2

OMT - 1

Year Version 2003: UML 2.0

2001: UML 1.4

1999: UML 1.3

Types of UML DiagramsTypes of UML Diagrams

Use Case DiagramUse Case Diagram::

Displays the relationship among actors and use Displays the relationship among actors and use cases.  cases. 

Class DiagramClass Diagram:: Describe the types of objects in the system and various kinds Describe the types of objects in the system and various kinds

of static relationship that exist among them.of static relationship that exist among them.

Sequence DiagramSequence Diagram:: Displays the time sequence of the objects Displays the time sequence of the objects

participating in the interaction.participating in the interaction.

Types of UML DiagramsTypes of UML Diagrams

Collaboration DiagramCollaboration Diagram

Displays an interaction organized around the Displays an interaction organized around the objects and their links to one another.objects and their links to one another.

State DiagramState Diagram

Displays the sequences of states that an object Displays the sequences of states that an object of an interaction goes through during its life in of an interaction goes through during its life in response to received stimuli, together with its response to received stimuli, together with its responses and actions.responses and actions.

Use Case Diagram(core components)

Actors: A role that a user plays with respect to the system,including human users and other systems. e.g.,inanimate physical objects (e.g. robot); an external system that needs some information from the current system.

Use case: A set of scenarios that describe an

interaction between a user and a system.

System boundary: rectangle diagram representing the boundary between the actors and the system.

Use Case Diagram(core relationship)Use Case Diagram(core relationship)

AssociationAssociation: communication between an actor and a use case; Represented by a solid line.

Generalization: relationship between one general use case and one specific use case.Represented by a line with a triangular arrow head toward the parent use case.

Use Case Diagram(core relationship)Use Case Diagram(core relationship)

Extend: a dotted line labeled <<extend>> with an arrow toward the base case. The extending use case may add behavior to the base use case. The base class declares “extension points”.

<<extend>>

Include: a dotted line labeled <<include>> beginning at base use case and ending with an arrows pointing to the include use case. The include relationship occurs when a chunk of behavior is similar across more than one use case. Use “include” in stead of copying the description of that behavior.

<<include>>

Use Case DiagramsUse Case Diagrams

Library System

Borrow

Order Title

Fine Remittance

ClientEmployee

Supervisor

• A generalized description of how a system will be used. 

• Provides an overview of the intended functionality of the system

Boundary

ActorUse Case

Use Case DiagramsUse Case Diagrams(cont.)(cont.)

(TogetherSoft, Inc)

Use Case DiagramsUse Case Diagrams(cont.)(cont.)

•Pay Bill is a parent use case and Bill Insurance is the child use case. (generalization)

•Both Make Appointment and Request Medication include Check Patient Record as a subtask.(include)

•The extension point is written inside the base casePay bill; the extending class Defer payment adds the behavior of this extension point. (extend)

ClassClass

► Each class is represented by a rectangle subdivided into three Each class is represented by a rectangle subdivided into three compartmentscompartments NameName AttributesAttributes OperationsOperations

► Modifiers are used to indicate visibility of attributes and Modifiers are used to indicate visibility of attributes and operations.operations. ‘‘+’ is used to denote +’ is used to denote PublicPublic visibility (everyone) visibility (everyone) ‘‘#’ is used to denote #’ is used to denote ProtectedProtected visibility (friends and derived) visibility (friends and derived) ‘‘-’ is used to denote -’ is used to denote PrivatePrivate visibility (no one) visibility (no one)

► By default, attributes are hidden and operations are visible.By default, attributes are hidden and operations are visible.► The last two compartments may be omitted to simplify the The last two compartments may be omitted to simplify the

class diagramsclass diagrams

An example of Class An example of Class

Account_Name- Custom_Name- Balance

+AddFunds( )+WithDraw( )+Transfer( )

Name

Attributes

Operations

Multiplicity and RolesMultiplicity and Roles

University Person

1

0..1

*

*

Multiplicity

Symbol Meaning

1 One and only one

0..1 Zero or one

M..N From M to N (natural language)

* From zero to any positive integer

0..* From zero to any positive integer

1..* From one to any positive integer

teacheremployer

Role

Role

“A given university groups many people; some act as students, others as teachers. A given student belongs to a single university; a given teacher may or may not be working for the university at a particular time.”

student

Class DiagramClass Diagram

Order

-dateReceived-isPrepaid

-number :String-price : Money

+dispatch()+close()

Customer

-name-address

+creditRating() : String()

Corporate Customer

-contactName-creditRating-creditLimit

+remind()+billForMonth(Integer)

Personal Customer

-creditCard#

OrderLine

-quantity: Integer-price: Money

-isSatisfied: Boolean

Product* 1

1

*Employee

*0..1

{if Order.customer.creditRating is"poor", then Order.isPrepaid must

be true }

* 1

Constraint

(inside braces{}}

Operations

Attributes

Name

Association

Multiplicity: mandatory

Multiplicity: Many value

Multiplicity: optional

Generalization

[from UML Distilled Third Edition]

class

Subtype2

Supertype

Subtype1

OO Relationships: Generalization

Generalization expresses a relationship among related classes. It is a class that includes its subclasses.

Regular Customer

Loyalty Customer

Customer Example:

Regular Customer

Loyalty Customer

Customer or:

OO Relationships: Composition

Class W

Class P1 Class P2

COMPOSITION Composition: expresses a relationship among instances of related classes. It is a specific kind of Whole-Part relationship.

It expresses a relationship where an instance of the Whole-class has the responsibility to create and initialize instances of each Part-class.

It may also be used to express a relationship where instancesof the Part-classes have privileged access or visibility tocertain attributes and/or behaviors defined by theWhole-class.

Composition should also be used to express relationship where instances of the Whole-class have exclusive access to and control of instances of the Part-classes.

Composition should be used to express a relationship wherethe behavior of Part instances is undefined without beingrelated to an instance of the Whole. And, conversely, thebehavior of the Whole is ill-defined or incomplete if one or more of the Part instances are undefined.

Whole Class

Part Classes

Automobile

Engine Transmission

Example

[From Dr.David A. Workman]

OO Relationships: OO Relationships: AggregationAggregation

Class C

Class E1 Class E2

AGGREGATION

Aggregation: expresses a relationship among instances of related classes. It is a specific kind of Container-Containee relationship.

It expresses a relationship where an instance of the Container-class has the responsibility to hold and maintain instances of each Containee-class that have been createdoutside the auspices of the Container-class.

Aggregation should be used to express a more informalrelationship than composition expresses. That is, it is anappropriate relationship where the Container and its Containees can be manipulated independently.

Aggregation is appropriate when Container and Containeeshave no special access privileges to each other.

Container Class

Containee Classes

Bag

Apples Milk

Example

[From Dr.David A. Workman]

Aggregation vs. CompositionAggregation vs. Composition

•CompositionComposition is really a strong form of aggregation •components have only one owner •components cannot exist independent of their owner •components live or die with their owner e.g. Each car has an engine that can not be shared with other cars.

•Aggregations may form "part of" the aggregate, but may not be essential to it. They may also exist independent of the aggregate. e.g. Apples may exist independent of the bag.

Sequence Diagram(make a call)Sequence Diagram(make a call)

Caller Phone Recipient

Picks up

Dial tone

Dial

Ring notification Ring

Picks up

Hello

Sequence Diagrams – Object Life SpansSequence Diagrams – Object Life Spans

► CreationCreation Create messageCreate message Object life starts at that pointObject life starts at that point

► ActivationActivation Symbolized by rectangular Symbolized by rectangular

stripesstripes Place on the lifeline where Place on the lifeline where

object is activated.object is activated. Rectangle also denotes when Rectangle also denotes when

object is deactivated.object is deactivated.► DeletionDeletion

Placing an ‘X’ on lifelinePlacing an ‘X’ on lifeline Object’s life ends at that Object’s life ends at that

pointpoint

Activation bar

A

BCreate

XDeletion

Return

Lifeline

Sequence DiagramSequence DiagramUser Catalog Reservations

1: look up ()

2: title data ()

3: [not available] reserve title ()

4 : title returned ()

5: hold title ()

5 : title available ()

6 : borrow title ()

6 : rem ove reservation ()

•Sequence diagrams demonstrate the behavior of objects in a use case

by describing the objects and the messages they pass.

•The horizontal dimension shows the objects participating in the interaction.

•The vertical arrangement of messages indicates their order.

•The labels may contain the seq. # to indicate concurrency.

Message

Interaction Diagrams: Collaboration diagramsInteraction Diagrams: Collaboration diagrams

User

Catalog

Reservations

start

1: look up2: title data

3 : [not available] reserve title

4 : title returned

5 : hold title

6 : borrow title

6: remove reservation

5: title available

•Shows the relationship between objects and the order of messages passed between them.  between them. •The objects are listed as rectangles and arrows indicate the messages being passed •The numbers next to the messages are called sequence numbers. They show the sequence of the messages as they are passed between the objects. •convey the same information as sequence diagrams, but focus on object roles instead of the time sequence.

State DiagramsState Diagrams ((Billing Example)Billing Example)

State Diagrams show the sequences of states an object goes through during its life cycle in response to stimuli, together with its responses and actions; an abstraction of all possible behaviors.

Unpaid

Start End

PaidInvoice created payin

gInvoice destroying

State DiagramsState Diagrams (Traffic light example)(Traffic light example)

Yellow

Red

Green

Traffic LightState

Transition

Event

Start

UML Modeling ToolsUML Modeling Tools ► Rational RoseRational Rose ( (www.rational.comwww.rational.com) by IBM) by IBM

► UML StudioUML Studio 7.1 ( 7.1 ( http://www.pragsoft.com/http://www.pragsoft.com/) by ) by Pragsoft Pragsoft CorporationCorporation

Capable of handling very large models (tens of thousands of Capable of handling very large models (tens of thousands of classes). Educational License US$ 125.00; Freeware version. classes). Educational License US$ 125.00; Freeware version.

► TogetherSoft Control Center; TogetherSoft SoloTogetherSoft Control Center; TogetherSoft Solo ( (http://www.borland.com/together/index.htmlhttp://www.borland.com/together/index.html) ) by by BorlandBorland

► ArgoUML (ArgoUML (free softwarefree software)) ((http://www.apple.com/downloads/macosx/development_tools/argouml.htmlhttp://www.apple.com/downloads/macosx/development_tools/argouml.html ) )

OpenSource; OpenSource; written in java written in java

► Others Others ((http://www.objectsbydesign.com/tools/umltools_byCompany.htmlhttp://www.objectsbydesign.com/tools/umltools_byCompany.html ) )

UML studio 7.1UML studio 7.1

ReferenceReference

1. 1. UML Distilled:UML Distilled: A Brief Guide to the Standard Object Modeling Language A Brief Guide to the Standard Object Modeling LanguageMartin FowlerMartin Fowler, , Kendall ScottKendall Scott

2. 2. Practical UML --- A Hands-On Introduction for DevelopersPractical UML --- A Hands-On Introduction for Developers http://www.togethersoft.com/services/practical_guides/umlonlinecourse/http://www.togethersoft.com/services/practical_guides/umlonlinecourse/

3.3. OO Concepts in UML. OO Concepts in UML. Dr. David A. Workman, School of EE and CS. UCF.Dr. David A. Workman, School of EE and CS. UCF.

4.4. Software Engineering Principles and Practice.Software Engineering Principles and Practice. Second Edition; Hans van Second Edition; Hans van Vliet.Vliet.