Activity Diagram

UML for Business Process Modelling (Activity Diagram)

1. UML Lecture
Series
UML SIG
UML for Business Modeling
(Activity Diagram)

2. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 2 (of 30)
Session Objectives
1.Explain the role of UML in modelling.
2.Demonstrate the use of activity diagrams in
business modeling.
3.Apply basic and advanced elements of activity
diagram notations.
4.Demonstrate the use of activity diagrams in
systems modeling.
5.Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

3. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 3 (of 30)
Keywords
Business modelling
Activity state
Transition
Triggerless transition
Synchronisation bar
Start state
Stop/End state
Branch
Guard
Fork
Join
Concurrent thread
Alternative thread
Conditional thread
System modelling

4. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 4 (of 30)
Session Objectives
•Explain the role of UML in modelling.
•Demonstrate the use of activity diagrams in
business modeling.
•Apply basic and advanced elements of activity
diagram notations.
•Demonstrate the use of activity diagrams in
systems modeling.
•Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

5. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 5 (of 30)
Why Model?
Captures Processes
Enhances Communication
Manages Complexity
Defines Architecture
Enables Reuse

6. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 6 (of 30)
Introduction to UML
UML is a language for visualising, specifying, constructing
and documenting the artifacts of a software intensive
system.
Open Specification by OMG (Object Management Group).
Current standard is UML 2.0. However, most students use
UML 1.4 which is sufficient for most academic projects.
UML is an analysis and design technique. It has to be used
together with a process in a development environment.

7. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 7 (of 30)
Overview of UML Diagrams

8. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 8 (of 30)
Thoughts to Ponder …
If you reuse code,
You'll save a load,
But if you reuse design,
Your future will shine.
Ralph E. Johnson.

9. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 9 (of 30)
… What is design? ... It’s where you stand with a foot
in two worlds—the world of technology and the world
of people and human purposes—and you try to bring
the two together.
Terry Winograd, “Bringing Design to Software”, Addison Wesley, Stanford
University and Interval Research Corporation, With John Bennett, Laura De
Young, and Bradley Hartfield, ISBN: 0-201-85491-0. 310
Thoughts to Ponder …

10. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 10 (of 30)
Session Objectives
•Explain the role of UML in modelling.
•Demonstrate the use of activity diagrams in
business modeling.
•Apply basic and advanced elements of activity
diagram notations.
•Demonstrate the use of activity diagrams in
systems modeling.
•Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

11. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 11 (of 30)
Business Modelling

12. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 12 (of 30)
Activity Diagram
In its basic form, an activity diagram is a simple and
intuitive illustration of what happens in a workflow, what
activities can be done in parallel, and whether there are
alternative paths through the workflow.
Historically, activity diagrams have mostly been used in
the business process modeling domain but are also
useful in system modelling.

13. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 13 (of 30)
Business
Modelling
This example is
a proposal
process, taken
from an
organization
that sells
telecom
network
solutions.

14. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 14 (of 30)
Session Objectives
•Explain the role of UML in modelling.
•Demonstrate the use of activity diagrams in
business modeling.
•Apply basic and advanced elements of activity
diagram notations.
•Demonstrate the use of activity diagrams in
systems modeling.
•Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

15. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 15 (of 30)
Basic
Notations
Start State
Activity State
Decision
(branch)
Synchronisation
bar
Stop/End State
Concurrent
thread
Alternative
thread
Transition

16. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 16 (of 30)
Activity Diagram - Notations
•Activity states, represent the performance of
a step within the workflow.
•Transition show what activity state follows
after another.
•Decisions (branch) for which a set of guard
conditions are defined. These are conditions
that must be met to trigger the transition.
•Synchronization bars, which you can use to
show parallel subflows. Synchronization
bars allow you to show concurrent threads -
fork or join.

17. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 17 (of 30)
Advanced
Notations
Guard
conditions can
be used to show
that one of a set
of concurrent
threads is
conditional.
Conditional Threads

18. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 18 (of 30)
Advanced
Notations
An activity state may
reference another activity
diagram, which shows the
internal structure of the
activity state by having a
nested activity graphs.
You can either show the
sub-graph inside of the
activity state or let the
activity state refer to
another diagram
Nested Activity Diagrams

19. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 19 (of 30)
Advanced
Notations
Nested Activity Diagrams

20. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 20 (of 30)
Advanced
Notations
The contents of an activity
diagram may be organized into
partitions (swimlanes) using solid
vertical lines.
A partition does not have a formal
semantic interpretation, but is, in
business modeling, often used to
represent an organizational unit
of some kind
Partitions

21. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 21 (of 30)
Session Objectives
•Explain the role of UML in modelling.
•Demonstrate the use of activity diagrams in
business modeling.
•Apply basic and advanced elements of activity
diagram notations.
•Demonstrate the use of activity diagrams in
systems modeling.
•Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

22. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 22 (of 30)
Systems Modelling
Just as you would use an activity diagram to show
the structure of a workflow, you could also use it to
show the structure of a flow of events of a system
use case

23. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 23 (of 30)
System
Modelling

24. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 24 (of 30)
Session Objectives
•Explain the role of UML in modelling.
•Demonstrate the use of activity diagrams in
business modeling.
•Apply basic and advanced elements of activity
diagram notations.
•Demonstrate the use of activity diagrams in
systems modeling.
•Awareness of typical mistakes made by students.
At the end of this session, YOU should be able to:

25. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 25 (of 30)
Common Mistake Made by Students
1.Business Modelling (activity diagram) which
appears like system modelling.
3.Students tend to be overly software centric paying
little emphasis on the underlying problem
statement which has to be mapped first (business
modelling).

26. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 26 (of 30)
True/False
•Business modelling is typically done before system
modelling.
•Alternative thread must go along with a branch.
•A branch can have at most THREE (3) alternative
threads
•Fork: One incoming transition and two or more
outgoing transition.
•Branch: Two or more incoming transition and one
outgoing transition.
•Synchronisation bar allow sequential threads.
•Conditional threads are also called triggered transitions
and must be shown with a guard condition.
•Transitions without guard conditions are called
triggerless transitions.

27. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 27 (of 30)
Summary
•Role of UML in systems modelling.
•Basic elements of activity diagrams are activity states,
transitions, decisions, and synchronization bars.
•Activity diagrams can be used to show concurrent
threads, and alternative threads, as well as
conditional threads in a workflow.
•Activity diagrams can be used to illustrate the
workflow of business processes - called business
modelling.
•Activity diagrams can be used to illustrate the flow of
events of a use case – for systems modelling.
•Awareness of typical mistakes by students.

28. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 28 (of 30)
Reference
Ericsson M. 2004, “Activity Diagram: What They Are
and How To Use Them” Level: Advanced, The Rational
Edge, IBM

29. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 29 (of 30)
Lab Session
Draw the
adjacent
diagram in
Visual Paradigm

30. UML SIG – UML Lecture Series UML for Business Process Modeling – Activity Diagram
UML SIG
Slide 30 (of 30)
Q & A
Question and Answer Session
Slide 30 (of 30)