Hi, Thanks for this, although I'm still missing something I think. The Order class I'm trying to define as an instance does have accessors and modifiers for all its properties, including the two defined on the superclass deftemplate that's already been created in the Rete. Given this, I'm still a little confused as to how the nil Value arises that causes the ClassCastException I'm getting and I'm still not sure how to correct it.
Is there anything else that would cause this exception to be thrown? Many thanks in advance Regards David ejfried Sent by: owner-jess-users@ To sandia.gov jess-users@sandia.gov cc 05/10/2005 14:34 Subject Re: JESS: Problem with definstance Please respond to [EMAIL PROTECTED] .gov I think David Firmin wrote: > I'm trying to create shadow facts that subclass a deftemplate that's > already been added to the Rete. When I try and add the java bean using > definstance I get a ClassCastException as follows: > > java.lang.ClassCastException > at jess.DefinstanceList.createNewShadowFact(DefinstanceList.java:206) > at jess.DefinstanceList.definstance(DefinstanceList.java:275) Jess is assuming that the given class "looks like" a subclass of the deftemplate -- i.e., if the template has slots foo and bar, then the class had better have getFoo() and getBar() methods. It can have additional properties as well, of course, as befits a subclass. In any case, this is a lousy error message -- Jess should explicitly detect and report this problem. --------------------------------------------------------- Ernest Friedman-Hill Advanced Software Research 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] -------------------------------------------------------------------- -------------------------------------------------------------------- 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] --------------------------------------------------------------------