I think Michel Drescher wrote: [Charset iso-8859-1 unsupported, filtering to ASCII...] > Folks, > > I read about Charlemagne (Jess 7.0) in this article > (http://www.devx.com/Java/Article/17651) and was immediately pleased by the > upcoming feature of Jess being able to reason over external resources (if I > got this right).
I don't think you did, actually. Current versions of Jess already can reason over external resources. What that article mentions is that Charlemagne will use "finders." A finder is a Java method you supply which fetches objects according to some description. The idea is that you might have a customer database including a million customers. Rather than having a million Customer objects in working memory, you just leave the customers in the database and write rules as if they were in working memory. Jess will use the finder method to fetch appropriate records. This is similar to what you can already do with backward chaining, but it's simpler to use and more efficient. > I want to implement a blackboard mechanism ... > I know this description is pretty unprecise, but since we are in a very > early stae of development, not everything is clear yet. > It's a description of a classic blackboard system. > Does anybody has an idea on how to implement this? Using JavaBeans to store > data in the blackboard and to simultaneously interface it with Jess (via > declass and definstance) seem to be right now the best solution I can see, > but I still doesn't like it - my impression is still that this has a "bad > smell" and can be improved. There's nothing wrong with doing it that way. If the individual pieces of data are static -- i.e., they don't have properties that change -- then you can use static definstances and so PropertyChangeListeners won't be needed, so the "Beans" can be very simple indeed. --------------------------------------------------------- Ernest Friedman-Hill Science and Engineering PSEs Phone: (925) 294-2154 Sandia National Labs FAX: (925) 294-2234 PO Box 969, MS 9012 [EMAIL PROTECTED] Livermore, CA 94550 http://herzberg.ca.sandia.gov -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
