02291: System IntegrationIntroduction to UML

Hubert Baumeisterhuba@dtu.dk

DTU ComputeTechnical University of Denmark

Spring 2019

What is the UML?

I Unified Modelling Language (UML)I Family of graphical notations for describing aspects of

(object-oriented) softwareI ”A picture is more than a thousand words”

I Based on a metamodelI Not a development processI UML is an open standard and an ISO standard

I managed by the Object Management Group(www.omg.org)

I Web resourcesI http://www.uml.org

UML’s history

I 1980sI Objects became main streamI OO methods and graphical notations

I Grady Booch, Peter Coad, Ivar Jacobson, Jim Odell, JimRumbaugh, Sally Shlaer and Steve Mellor, RebeccaWirfs-Brock, . . .

I 1990sI Grady Booch, Ivar Jacobson and Jim Rumbaugh at

RationalI First version of the UML (UML 0.8)

I 1996I The Object Management Group (OMG)I Driven by tool vendors!

I Tool interoperability!I 1.x with 1.4 and 1.5 being widely used

I 2005I UML 2.0 ISO standard

Notations and Metamodels

I UML consists ofI a set of graphical notationsI and a single metamodel

Example of a class diagram

StartRoomSpecialRoom

Level

Player

Room

PersonalObject

nextLevel*

0..1

connectedTo*

*

1

1..* 1

*

0..1

*

*inventory

Metamodel Excerpt

UML Superstructure Specification, v2.4.1 29

Figure 7.12 - Classes diagram of the Kernel package

Classifier

Class

Operation

Classifier

StructuralFeature

Association+ isDerived : Boolean = false

ClassifierRelationship

ValueSpecification

Type

Property+ isDerived : Boolean = false+ isReadOnly : Boolean = false {redefines isReadOnly}+ isDerivedUnion : Boolean = false+ /default : String [0..1]+ aggregation : AggregationKind = none+ /isComposite : Boolean+ isID : Boolean = false

«enumeration»AggregationKind

nonesharedcomposite

* + class

* + /superClass

{subsets classifier}

{redefines general}

0..1

+ class

*

+ ownedOperation

{subsets featuringClassifier,subsets redefinitionContext,subsets namespace}

{ordered, subsets feature,subsets redefinableElement,subsets ownedMember}

0..1

+ class

*

+ nestedClassifier

{subsets namespace, subsetsredefinitionContext}

{ordered, subsets ownedMember,subsets redefinableElement}

0..1 + association

*+ navigableOwnedEnd

{subsets owningAssociation}

{subsets ownedEnd}

0..1

+ owningAssociation

*

+ ownedEnd

{subsets association,subsets featuringClassifier,subsets namespace, subsetsredefinitionContext}

{ordered, subsets memberEnd, subsets feature,subsets ownedMember, subsets redefinableElement}

0..1

+ association

2..* + memberEnd

{subsets memberNamespace}

{ordered, subsets member}

0..1+ owningProperty

0..1

+ defaultValue

{subsets owner}

{subsets ownedElement}

*

+ association

1..*

+ /endType{subsets relationship}

{ordered, readOnly,subsets relatedElement}

0..1 + class

*

+ ownedAttribute

{subsets classifier, subsets namespace}

{ordered, subsets attribute,subsets ownedMember}

**

+ subsettedProperty

0..1 0..1 + /opposite

*

+ property

*

+ redefinedProperty

{subsets redefinableElement}

{subsets redefinedElement}

Metamodel

I Abstract syntax of UML diagramsI Describes the concepts of UML elements

I e.g. class, association, . . .I concepts are mapped to notations

I e.g. the concept of a class is mapped to rectangle withsubcompartments

I Metamodel written in MOF (Meta-Object Facility)I Basically UML class diagrams→ MOF can be used to defined ones own modelling language→ Course Software Engineering II (02162)

I The metamodel is important for model exchangeI XMI (XML Metadata Interchange)

The meaning of UML

I The abstract syntax / concepts: OK→ metamodel

I The meaning of the concepts: not well-definedI Meaning of class?I Execution of activity diagrams and state machines

I Semantic variation pointsI Left open in the standardI Tool vendors choose meaning

Ways of using the UML

I SketchI Informal use→ Use of whiteboards, simple graphic editors

I BlueprintI Forward Engineering: e.g. create class stubs→ Use of CASE tools

I Programming languageI Executable UMLI Problems

I How to describe the behaviour?

→ Use of CASE tools

Ways of using the UML

I SketchI Informal use→ Use of whiteboards, simple graphic editors

I BlueprintI Forward Engineering: e.g. create class stubs→ Use of CASE tools

I Programming languageI Executable UMLI Problems

I How to describe the behaviour?

→ Use of CASE tools

Ways of using the UML

I SketchI Informal use→ Use of whiteboards, simple graphic editors

I BlueprintI Forward Engineering: e.g. create class stubs→ Use of CASE tools

I Programming languageI Executable UMLI Problems

I How to describe the behaviour?

→ Use of CASE tools

UML is not enough

I UML is a general purpose modelling languageI UML can be extended

I lightweight (UML profile)I heavy weight

→ Use the modelling language best suited for your purpose

UML Diagrams (I)

I Structure DiagramsI Class Diagram

I Class, features, and relationshipsI Object Diagram

I Example configuration of instancesI Package Diagram

I Hierarchical structure for modelsI Component Diagram

I Structure and connections of componentsI Deployment Diagram

I Deployment of artifacts to nodesI Composite Structure Diagram

I Runtime decomposition of a class

UML Diagrams (II)

I Behaviour DiagramsI Use-Case Diagram

I How users interact with a systemI Activity Diagram

I Procedural and parallel behaviourI State Machine Diagram

I How events change an object over its lifeI Interaction Diagram

I Sequence Diagram: Interaction between objects; emphasison sequence

I Communication Diagram (formerly called collaborationdiagram): Interaction between objects; emphasis on links

I Interaction Overview Diagram: Mix of sequence and activitydiagram

I Timing Diagram: Interaction between objects; emphasis ontiming

Focus of the course

One car, many models (abstractions)

Focus of the courseOne system, many models (abstractions)

Different Views on the systemI Functionality: Use Case diagram, state machines, activity

diagram, . . .I Structure: Component diagram, Class diagramI Validation: Interaction diagram

Library Example: Detail of Use case borrow book

Use case diagram

User

LibrarySystem

borrow book

return book

search for book

Use case borrow bookBasic course of events:

1. User scans his library card2. User selects check out3. User scans the book4. System confirms loan

Implementation: Component Diagram

<<inter face>>LibraryInterface

scanLibraryCard()checkOutscanBook()checkIn...

LibraryInterface

LibrarySystem

Implementation: Class Diagram

Library SM

user okuser ok

can borrow?

...

...

book scannedUser scannedIdlecheckOut

[not cb] / return "book can't be borrowed"

scanBook(l)

[cb] / b.checkOut(); return "ok"

/ cb := bor.canBorrow()

[users->contains(l)]

[not users->contains(l)] / return err-msg

scanLibraryCard (l)

Use Case success scenario realisation

loop [foreach b' in bor->books]

Use case borrow book : User interactions

Use case borrow book :Basic course of events

1. User scans his library card2. User selects check out3. User scans the book4. System confirms loan

sd: borrow book success

scan librarycard(bor)

t rue

checkOut()

scan book(b)

canBorrow()

isOverdue()

false

loop

true

checkout(bor)

t rue

t rue

loop

UserLibrary bor:Borrower

[b in bor.books]

b1:Book b2:Book

Library SM

user okuser ok

can borrow?

...

...

book scannedUser scannedIdlecheckOut

[not cb] / return "book can't be borrowed"

scanBook(l)

[cb] / b.checkOut(); return "ok"

/ cb := bor.canBorrow()

[users->contains(l)]

[not users->contains(l)] / return err-msg

scanLibraryCard (l)

loop [foreach b' in bor->books]