Objects From The Users World

In the early days of OO it was believed that all objects in an OO program should be derived from ObjectsFromTheUsersWorld.

And then we discovered that we were helping users create a new world.

And then we found we had to fix the broken world we created last time round.

How does this relate to ChristopherAlexander's pattern ThingsFromYourLife??

Actually, I think this belief was promulgated mainly by a subset of methodologists who didn't happen to think about all the classes involved in window system interaction, file system interaction, database interaction, etc. - not to mention the more modern issues of network interaction, distributed object middleware interaction, and whatnot. BusinessObject classes are still very important and valuable (and in fact still under-emphasized), IMHO, but percentage-wise they form only a minority of the classes in an application. GemStone's AdvancedApplicationArchitectureTeam made a presentation on exactly this topic - see http://www.gemstone.com/news_events/online_seminar.html. -- RandyStafford