1. Agile Modeling
From Anti-Patterns to Best Practices
Agile Tour Vilnius, 6 October 2011
1

2. About MagicDraw
> A popular UML-based modeling tool developed in Lithuania
> Available since 1998
> Over 500.000 downloads in 90 countries
> Standard-compliant and highly customizable platform
> MagicDraw R&D teams uses a lot of Agile practices
More info: www.magicdraw.com
Awards
Jolt Jolt Best Java Best Team
Best Java Development
Productivity Productivity Modeling
Database Tool Tool
Winner Winner Tool
2

3. About Speakers
Darius Šilingas, Rokas Bartkevičius,
Head of Solutions Solution Architect
Department @ No Magic Europe
@ No Magic Europe
> 7 years modeling consultancy
> training and consultation sessions done in close to 100
organizations from 20 countries
3

4. Agenda
 UML vs. Agile
 Anti-Patterns vs. Best Practices
 Wrap-up
4

5. About UML
 UML is widely acknowledged as de
facto standard for software modeling
 UML does not specify a method, just
the modeling language elements
 UML receives a lot of criticism for
being too complicated and difficult to
apply
 A typical modeler needs ~20% of
UML applied with a well-defined
method
5

6. Agile Manifesto
We are uncovering better ways of developing software by doing
it and helping others do it. Through this work we have come
to value
 Individuals and interactions over
processes and tools
 Working software over comprehensive documentation
 Customer collaboration over contract negotiation
 Responding to change over following a plan
That is, while there is value in the items on the right, we value
the items on the left more.
6

7. Modeling May Help
• It’s not about communication, it’s about the way
how you communicate
• Model could help
• Picture is worth
1000 words
7

8. Agile and UML: Friends or Foes?
Agile practitioners tend to not use modeling and UML
 They focus on coding
 Quite often, a big picture is lost
Our experience shows that code is not enough
Modeling is still a valuable tool in agile organizations for
capturing domain concepts and processes, system
requirements and high level designs
From our consulting experience, we conclude that a bad
name for UML results from common bad practices
8

9. Top 5 Anti-Patterns
1. Code abstraction level
2. Too complex diagrams
3. Misuse of UML concepts
4. No reuse of model elements
5. Mixed modeling styles
9

10. Anti-Pattern #1: Code Abstraction Level
10

11. Issues
Duplicating information available in code
Dependence on technical platform
Complex and difficult to read diagrams
11

12. Best Practice #1
Raise level of abstraction
12

13. Anti-Pattern #1: Code Abstraction Level
13

14. Refactoring #1
14

15. Encapsulate Technical Platform Details in Transformation
CREATE TABLE Test (
title varchar (255) NOT NULL,
instructions varchar (255) NOT NULL,
id integer PRIMARY KEY,
fk_Class integer NOT NULL,
fk_Teacher integer NOT NULL,
FOREIGN KEY(fk_Class)
REFERENCES Class (id),
FOREIGN KEY(fk_Teacher)
REFERENCES Teacher (id));
CREATE TABLE Question (
description varchar (255) NOT NULL,
id integer PRIMARY KEY
...);
CREATE TABLE QuestionTest (
fk_Question integer,
Transformation Template (VTL) fk_Test integer,
... );
15

16. Anti-Pattern #2: Too Complex Diagrams
16

17. ~450 Actions
~950 Control Flows
17
17

18. Issues
Difficult to read and understand
Hides incompleteness issues
Difficult to maintain
Everything should be made as simple as possible,
but not simpler. Albert Einstein
18

19. Best Practice #2
Use several levels of detail
www.implementingscrum.com
19

20. Anti-Pattern #2: Too Complex Diagrams
20

21. Refactoring #2: Overview
21

22. Refactoring #2: MagicTest
22

23. Refactoring #2: MagicTest Q & A
23

24. Refactoring #2: MagicUniversity
24

25. Anti-Pattern #3: Misuse of UML Concepts
25

26. Issues
Inconsistency in modeling conventions
Ambiguous understanding
Redundant stereotyping
26

27. Best Practice #3
Apply consistent modeling method
based on UML subset
27

28. Anti-Pattern #3: Misuse of UML Concepts
28

29. Refactoring #3: Main Use Cases
29

30. Refactoring #3: Actions in the Workflow
30

31. Anti-Pattern #4: No Reuse of Model Elements
31

32. Issues
Duplicated/redundant information in
separate architecture views
Difficult to maintain consistent model
32

33. Best Practice #4
Integrate architecture views
33

34. Anti-Pattern #4: No Reuse of Model Elements
34

35. Refactoring #4: Structural View
35

36. Refactoring #4: Implementation View
36

37. Refactoring #4: Behavioral View
37

38. Anti-Pattern #5: Mixed Modeling Styles
38

39. Issues
Difficult to read and understand
39

40. Best Practice #5
Establish modeling conventions
40

41. Anti-Pattern #5: Mixed Modeling Styles
41

42. Refactoring #5
42

43. Top 5 Best Practices
1. Raise level of abstraction
2. Use several levels of detail
3. Apply consistent modeling method based
on UML subset
4. Integrate architecture views
5. Follow modeling conventions
43

44. How to Establish Agile Modeling Culture?
 Define your modeling solution
– Subset of UML
– Consistent modeling method
– Simple modeling environment
 Identify modeling champions
 Apply Agile programming practices in modeling
 Share anti-patterns and best practices
 Adopt modeling incrementally
44

45. Suggested Readings
 A whitepaper Efficient UML from Anti-
Patterns to Best Practices is scheduled for
December 15
 Refactoring BPMN Models: from Bad
Smells to Best Practices and Process
Patterns in BPMN 2.0 Handbook
 Agile Modeling
 Elements of UML 2.0 Style
45

46. Thank You for Attention!
Let’s keep in touch:
Rokas Bartkevičius
e-mail: rokas.bartkevicius@nomagic.com
Skype: rokas.bartkevicius
http://lt.linkedin.com/in/rokasbartkevicius
Darius Šilingas
e-mail: darius.silingas@nomagic.com
Skype: darius.silingas
http://lt.linkedin.com/in/dariussilingas
46