These are the slides for the second lecture of the course "Model-Driven Software Development" taught at Delft University of Technology in the academic year 2009-2010.

1. Domain Analysis
& Data Modeling
Lecture2
Course IN4308
Eelco Visser
Master Computer Science
http://eelcovisser.org Delft University of Technology
Thursday, February 11, 2010

2. Course Goal
Learn to design and implement
domain-specific languages
Understand DSL design choices and make
reasoned decisions about their application
Thursday, February 11, 2010

3. Model-Driven Software Development
Problem
DSL HLL Machine
Domain
domain-specific models reduce gap between
problem domain and implementation
Thursday, February 11, 2010

4. Why domain-specific languages?
Domain-specific models
- increase level of abstraction
- are closer to problem domain
- are smaller
- are easier to write
- are easier to maintain
Thursday, February 11, 2010

5. What is a model?
A model
- is a simplification of a system
★ abstraction, description, specification, information
- can answer questions in place of actual system
★ analysis, inference, predictions
- is used for a purpose
★ understanding, planing, risk analysis, ...
Thursday, February 11, 2010

6. How are ‘models’ different from ‘code’
- Models are just another form of code
- Are models better than code?
★ no, models provide different level of abstraction
★ depends on the purpose
★ how well does DSL fit purpose
★ should be easier to analyze
- Continuum of abstractions
- Abstraction => giving up control
Thursday, February 11, 2010

7. “Far better at some key things”
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8. How do we make DSLs?
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9. Syntax
Checks
described by
Model DSL Editor
consists of
generate Transformation
Software
System Generator
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10. What makes a DSL?
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11. What makes a DSL?
The Domain
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12. What is a domain?
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13. Domain Engineering is the activity of collecting,
organizing, and storing past experience in building
systems or parts of systems in a particular domain in
the form of reusable assets (i.e. reusable work
products), as well as providing an adequate means for
reusing these assets (i.e., retrieval, qualification,
dissemination, adaptation, assembly, and so on) when
building new systems
Source: Czarnecki & Eisenecker, Generative Programming, 2000
Thursday, February 11, 2010

14. Domain Engineering
domain domain system family
knowledge model architecture
Domain Domain Domain
Analysis Design Implementation
DSLs
requirements components
generators
Requirements Product Integration
Analysis Configuration and Test
requirements features configuration product
Application Engineering
Source: Czarnecki & Eisenecker, Generative Programming, 2000
s Thursday, February 11, 2010

15. Application Domain = Family of Systems
Identify
- Commonality
★ What is the same in all systems?
★ Can be reused between applications
★ Standard components
★ Generated code
- Variability
★ What is different between systems?
★ Needs to be defined for each application
★ Using domain-specific language
Thursday, February 11, 2010

16. Domain analysis in
application engineering
implement
Problem Solution
Domain validate
Domain
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17. Domain: “A sphere of knowledge, influence, or activity”
“The subject to which the user applies a
program is the domain of the software”
Eric Evans, Domain-Driven Design, 2004
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18. System
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19. Interaction Design
Domain-Driven Design
Data Model Design
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20. Interaction Design
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21. X + Computer = Computer
Cognitive Friction
Dancing Bearware
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22. Analysis
Software design driven by developers
- implementation model is leading
- convenient for developer, not for user
- developers drive design ‘from the back seat’
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23. Thursday, February 11, 2010

24. User Personas
Goals (not Tasks)
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25. Polite software is
★ interested in me
★ forthcoming
★ has common sense
★ anticipates my needs
★ is responsive
★ is taciturn about its problems
★ is well informed
★ is perceptive
★ is self-confident
★ stays focused
★ is fudgable
★ is trustworthy
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26. Interaction Design
requires
Big Up Front Design
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27. How can we integrate interaction design
in software engineering?
Can programmers be interaction designers?
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28. Some lessons that I have tried to apply
- Direct manipulation
★ edit where you view
- No confirmations
★ no destructive, catastrophic actions
- No inaccessible actions/links
★ apply access control to source of navigation
- Limitations for user should be based on policy
★ policy: rules based on domain requirements
★ mechanism: inconvenient to implement
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29. Student
Course
University
Guests Management Administration
System
Lecturer
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46. What goals does/should ‘The Department’ support?
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48. “Every software program relates to some
activity or interest of its use. That subject
area to which the user applies a program
is the domain of the software”
Eric Evans, Domain-Driven Design, 2004
Thursday, February 11, 2010

49. “A model is a selectively simplified and
consiously structured form of knowledge”
Eric Evans, Domain-Driven Design, 2004
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50. Ubiquitous Language: “a language
structured around the domain model and
used by all team members to connect all the
activities of the team with the software”
Eric Evans, Domain-Driven Design, 2004
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51. Thursday, February 11, 2010

52. [Course]-*[Student]
[Course]-*[Lecturer]
[Course]-*[Assistant]
[Course]-*[Lecture]
[Course]-*[Assignment]
[Assignment]-*[Submission]
[Submission]1-1..[Student]
[Lecture]-[Slides]
[Lecture]-[Notes]
http://yUML.me: a DSL for drawing UML diagrams
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53. Thursday, February 11, 2010

54. Collaboration on Assignments
Scenario 1
- Piet starts submission for Design 1
- Jan starts submission for Design 1
- Piet and Jan want to work together
on Design 1
Scenario 2
- Piet, Jan work together on Design 1
- They want to split
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55. Binding Students to Submissions
- Creating submissions
★ should be enrolled
- Can be partner if
★ no active submission
★ #students < limit
- Start submission if
★ not part of active submission
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56. Submissions & Deadlines
- Edit assignment after submission?
★ before deadline
★ after deadline
★ after/during grading
- Status of assignment not submitted before
deadline?
- Submitting partial assignments?
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57. Domain Model = Concepts + Interaction
System
Domain analysis is more than drawing a class diagram
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58. A domain-specific language
for domain-driven design
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59. entities with properties
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66. ‘Physical’ Data Models
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67. From conceptual to physical data model
In memory
- objects
- hash maps
Persistent data
- Records in RDBS
- XML
- JSON
- Text (csv)
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68. Schedule
Lab this week:
★ WebDSL tutorial => submit page index
★ Make design proposal for a web application
★ Entity declarations for your web application
Read/think:
★ Read: interaction design, domain-driven design
★ Case 1: analysing issues in digital library domain
Next week
★ Web Abstractions
Thursday, February 11, 2010