Friday, January 09, 2004

Skills for the Agile Designer

Rebecca Wirfs-Brock’s thoughts on how to go about becoming an agile designer - Skills for the Agile Designer [PDF].

This is really an interesting mix of stuff. References to Coad’s Archetypes and Steve Palmer also gets a mention. This is the first time I’ve seen work attempting to merge Coad and Wirfs-Brock material. [Peter and Rebecca are widely regarded as the two best domain modelers - at least of the 1990s - because they spent the most time out in the field building real models for real big companies.] Also cited in this presentation: Martin Fowler, Objectory/RUP’s Entity-Control-Boundary (something I just never did buy into), and Michael Jackson’s well respected Problem Frames (a book I could never get into). It’s an eclectic mix which shows that Rebecca Wirfs-Brock is not afraid to look beyond her own work and pull the best ideas together to move towards an agile design solution.

Thursday, January 08, 2004

Getting the Blues

When I used to live in Kansas City, I regret that I was too busy working (it was the telecom boom) to get a chance to listen to much blues music. I missed a great opportunity.

Recently, I’ve been mentoring a team on how to “get” a different kind of blues - Peter Coad’s “blue” Description Archetype! Steve Palmer wrote this excellent article on the topic. The same technique appears in Nicola, Mayfield and Abney’s Streamlined Object Modeling Chapter 6 Object Inheritance though it has a different name.

Why do patterns like these matter?

Simply put good functional architecture provides better encapsulation, better division of responsibilities and more flexibility. The <<plug-in point>> pattern at the end of the Palmer article is a particularly powerful one which provides solutions to carrier class code maintenance and evolution issues.

Agility is about more than just working practices. Agility is at least a 3 sided problem of working practices, architecture and tools. Agile methods which ignore architecture leave future profits on the table. Agile managers concerned with better business performance need to look beyond working practices and insure that their teams are learning and using best-of-breed analysis and architecture methods and using tools which best facilitate the flow of value through their system of software engineering.

[Update on the OMG’s Business Modeling RFP - My moles in the know tell me that the Coad, Nicola, Mayfield, Palmer et al Archetype and Pattern Player methods are getting strongly represented. This means that my desire to see Ronald Ross’ Business Rules Approach merged with Coad’s domain modeling approach has a chance of happening and becoming an industry standard.]

Tuesday, January 06, 2004

OMG Issues RFP for Business Rules

Well not quite yet! But this is good news - I think. OTOH, knowing how slow the OMG has gotten in recent years, maybe not.

No! It is definitely good news. The more mainstream the notion of separate business rules gets, the better it must be for software development.

More interesting is the forthcoming Business Modeling RFP…

<!—StartFragment—>The major focus of the Nashville meeting, which was continued at the London meeting of the OMG later in November, was on the Business Modeling RFP.  Discussion about business modeling had started at the September OMG meeting in Boston.  Development of the paper on Architecture of Business Modeling is proceeding, to scope out coordinated RFPs that will together provide robust standard metamodel for business modeling.  So that we are on the same page about what is meant by ‘business modeling’ in this context, below is the working definition being used by the OMG Business Rules SIG and Business Enterprise Integration Domain Task Force, who is the issuer of the RFPs drafted by the BR SIG.

and I really like the definition of a Business Process…

<!—StartFragment—>business process  category of business model that focuses on the transformative aspect of the business—that is, value chains or sequences of functions that take raw materials or other resources and transform them in such a way to add value for people inside and/or outside the business.

My work with Peter Coad’s color modeling with Archetypes [see Chapter 1 of Java Modeling PDF] has given a deep insight into business modeling. I have argued that chains of Peter’s <<Moment-Interval>> archetypes represent business processes and the definition from the OMG seems to reflect that - which is good. I first presented the Coad technique at an OMG meeting in Orlando in 2000. [This is the same presentation [PPT] that I gave at the Sprint Object Oriented User Group Conferences in Dallas, Kansas City and Reston in the same year]. There wasn’t much of an audience for it then though those who came to the presentation were excited about it.

I really hope that my friends at Borland are making an effort to get the work of Coad, Nicola, Mayfield and Palmer into the mix. I would really like to see Coad’s Business Archetypes become part of the standard and color modeling develop a wider audience.