1. From Relational ClassSheets to UML+OCL
Já
come Cunha, Joã Saraiva
o Joã Paulo Fernandes
o
Universidade do Minho Universidade do Minho &
Portugal Universidade do Porto
Portugal
HASLab Talk, March 21, 2012

2. From Relational ClassSheets to UML+OCL
Já
come Cunha, Joã Saraiva
o Joã Paulo Fernandes
o
Universidade do Minho Universidade do Minho &
Portugal Universidade do Porto
Portugal
SAC-SE 2012
March 26-30, Riva del Garda (Trento), Italy

3. Agenda
● Introduction
● ClassSheets
● Extending ClassSheets: Relational ClassSheets
● Mapping Relational ClassSheets to UML Class
Diagrams + OCL
● Conclusions and Future Work 3

4. Introduction
4

5. Spreadsheets are widely used
5
Image taken from http://www.flickr.com/photos/cosmosfan/2414002070/

6. Spreadsheets contain many errors
6
Image taken from http://www.computerrepairmaintenance.com/secrets-to-fixing-computer-problems/

7. Model-based approach promises good results
7
Images taken from http://www.getopt.org/ecimf/contrib/onto/REA/REA-UML.gif and http://www.telecom-lille1.eu/people/Vanwormhoudt/siteEMFOCL/tutoriel/TutorialEMFOCL1.htm
and http://weblogs.asp.net/scottgu/archive/2006/07/12/Tip_2F00_Trick_3A00_-Online-Database-Schema-Samples-Library.aspx

8. ClassSheets – Spreadsheet Models
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9. ClassSheets to the Rescue!
● Introduced by Engels and Erwig to model the
business logic of spreadsheet data
● They allow to model spreadsheets using object-
oriented concepts
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10. Vertically Expandable Tables
ClassSheet Model Spreadsheet Data
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11. Horizontally Expandable Tables
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12. Relationship Tables
ClassSheet Model
Spreadsheet Data
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13. How does it Work?
Initial empty spreadsheet is generated
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14. 14

15. Limitations
● Does not allow to specify several constraints
● Specially database-like features
● In fact, the example shown could not be
completely characterized by the original version
● We will show how to extend ClassSheets
● Also, tools to further analyzes are missing (for
example, test properties)
● The mapping to UML Class Diagrams will make
available an entire new set of tools 15

16. Extending ClassSheets: Relational ClassSheets
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17. Unique Values
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18. Foreign Key
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19. Mapping Relational ClassSheets to
UML Class Diagrams + OCL
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20. Small Example
ClassSheet UML
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21. Running Example (ClassSheet)
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22. Running Example (UML)
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23. Generated OCL Sample
context Pilots
inv pkPilots : Pilots.allInstances->
forAll(a1, a2 | a1 <> a2 implies
a1.id <> a2.id)
context planeskey : PlanesKey inv
fkPlanesKey : Planes.allInstances->
exists(a |
a.n-number = planeskey.planes_key)
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24. (Part of) The Implementation
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25. Conclusions and Future Work
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26. Conclusions
● We have extended the original ClassSheets
with relational features
● With the extension we can now specify
database-like spreadsheets
● UML Class Diagrams + OCL can now be
automatically derived from ClassSheets
● A more broad specification language and tools
are now available
26

27. Future Work
● USE allows to add pre and post-conditions to
on operation on UML model
● This could be translated to formulas/macros in
spreadsheets systems
● Map existing UML Class Diagrams models to
ClassSheets
27

28. Thank you!
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