Jcome Cunha, Joo Saraiva

Universidade do MinhoPortugal

Joo Paulo Fernandes

Universidade do Minho & Universidade do PortoPortugal

HASLab Talk, March 21, 2012

From Relational ClassSheets to UML+OCL

Jcome Cunha, Joo Saraiva

Universidade do MinhoPortugal

Joo Paulo Fernandes

Universidade do Minho & Universidade do PortoPortugal

SAC-SE 2012March 26-30, Riva del Garda (Trento), Italy

From Relational ClassSheets to UML+OCL

Agenda

IntroductionClassSheets

Extending ClassSheets: Relational ClassSheets

Mapping Relational ClassSheets to UML Class Diagrams + OCL

Conclusions and Future Work

Introduction

Spreadsheets are widely used

Image taken from http://www.flickr.com/photos/cosmosfan/2414002070/

Spreadsheets are widely used

Spreadsheets are widely used

Spreadsheets contain many errors

Image taken from http://www.computerrepairmaintenance.com/secrets-to-fixing-computer-problems/

Model-based approach promises good results

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

Only after a model is done instances are created

Has been showing good results in other fields

Not only in CS, but in more stable areas like civil engineering

This approach is not followed when developing spreadsheets

ClassSheets Spreadsheet Models

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

Vertically Expandable Tables

Spreadsheet Data

ClassSheet Model

Horizontally Expandable Tables

Relationship Tables

ClassSheet Model

Spreadsheet Data

Initial empty spreadsheet is generated

How does it Work?

From a ClassSheet an initial spreadsheet is generated

This generated spreadsheet guides users in introducing correct dataThe spreadsheet includes mechanisms that guarantee that the spreadsheet data always conforms to the model after an user update

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

Limitations

Extending ClassSheets: Relational ClassSheets

Unique Values

Foreign Key

Mapping Relational ClassSheets to
UML Class Diagrams + OCL

Small Example

ClassSheet UML

Running Example (ClassSheet)

Running Example (UML)

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)

Generated OCL Sample

(Part of) The Implementation

Baseado em haskell

Integrado no OO

Clicanca-se em botoes

Espetacular

Basic

Conclusions and Future Work

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

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

Thank you!