Lecture 10 Other UML Notations

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Lecture 10Other UML Notations

• Activity Diagrams
• Documenting workflows
• Basic Notation
• ATM Case Study withdrawal use-case
• Packages and Subsystems
• Implementation Diagrams (very briefly)
• Component diagrams
• Deployment diagrams

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UML Activity Diagrams

• Used to document workflows
• Modelling business activities or systems
• Modelling activities within/between use-cases
• Detailed description of operations in classes
• Similar notation to UML statechart diagrams
• Activities (action states)
• States
• Transitions

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Activity Diagrams State Diagrams

• Notationally, very similar
• Important to distinguish purpose/use
• State diagrams
• behaviour of individual objects/components
• show state transitions triggered by events
• Activity diagrams
• behaviour within systems/organizations
• transitions between activities (work flows)

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Activity Diagrams Basic Notation
Start state
Activities
Transitions
Simple Activity Diagram with start and stop states
Final state
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Activity Diagrams Decision Points
Decision points allow branching depending on a
condition
Guard condition
Decision point
Invalid PIN
Valid PIN
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Activity Diagrams Swimlanes
Swimlanes are a useful notation for indicating
where an activity takes place
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ATM Case Study Workflow for Withdrawal Use-Case
Withdraw Cash
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ATM Case StudyElaborated Use-Case Description
Actor
System
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ATM Case Study Activity Diagram for Withdrawal
ATM Customer
ATM System
Select withdrawal
Display menu
Insufficient funds
Select amount
Sufficient funds
User takes card
Return card
Notify user
Dispense cash
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Packages and Subsystems

• Package a collection of model elements
• grouping semantically related elements
• analysing system architecture
• hiding irrelevant detail on a diagram
• Subsystem special sort of package
• representing units of the physical system
• developing components of the design

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Packages Organising Model Elements
Account System
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ATM Case Study Layered Architecture
ATM System
Packages represent different aspects of system
architecture. Packages can be nested. Note also
the asymmetry of dependencies between packages.
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UML Component Diagrams
Relationship between components
ltltcommunicatesgtgt
ATMControl.java
Component diagrams show how physical units such
as files, executables, etc. are related
Notation for components
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UML Deployment Diagrams
Communication association
Deployment diagrams model configuration of
hardware elements
Nodes
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Summary

• Activity diagrams
• Model workflows
• Transitions between activities
• Use-case modelling/business modelling
• Packages
• Group logically related units
• Implementation diagrams
• Component diagrams document physical elements
• Deployment diagrams document hardware elements