Hi,

Thanks for your interest.  You're right about what the rule engine does. 
For some reason I can't get to haley right now, I'll check again later.  I
haven't been able to find out what jsr 94 is/will be proposing.  Does
anyone have any information?

Thanks
David Jencks
On 2001.04.18 19:28:59 -0400 Vladimir Blagojevic wrote:
> Hey,
> 
> I saw your message too.  However, I am so busy this week that I can not
> devote any time to JBoss. 
> 
> As I understand Rule engines are some sort of interpreter for
> if-then-else
> logic.  I assume that they are going to be used mostly in business logic
> of
> your beans. I assume that instead of some if-then-else spaghetti , rule
> engine intercepts state mutations of an object , checks the rules against
> it and fires the rule event.
>  
> Is this right?
> 
> Some good intro I found here: www.haley.com
> 
> Also there is jsr 94 about rule engine.
> 
> Vlada
> 
> 
> 
> On 2001.04.18 19:54 David Jencks wrote:
> > Hi,
> > At least one person saw my message.
> > Thats one of the questions I was asking.  A couple of months ago Marc
> > suggested someone write a rule engine integration for jboss, so I
> > volunteered.  Although there is a java community process group working
> on
> > an integration standard, I couldn't find out what they're up to, and
> I've
> > had little luck finding out what kind of rules people might want to
> use. 
> > Any references or information or examples would be greatly appreciated.
> > 
> > Thanks
> > David Jencks
> > On 2001.04.18 16:27:50 -0400 Jason Dillon wrote:
> > > What is a rule engine used for in real world applications?  Could you
> > > give
> > > an example (other than "compute factorials and fibonacci numbers")?
> > > 
> > > --jason
> > > 
> > > On Wed, 18 Apr 2001, David Jencks wrote:
> > > 
> > > > Hi,
> > > >
> > > > I am pleased to announce that I have a working rule engine
> > integration
> > > > between JBoss and JEOPS (http://sourceforge.net/projects/jeops/). 
> I
> > > have
> > > > made the source available at http://home.earthlink.net/~davidjencks/.
> > > > There are tar.gz and zip versions.  Please follow the instructions
> in
> > > the
> > > > README.  You may need to change executable permissions on some
> > scripts
> > > to
> > > > get the examples to run.
> > > >
> > > > I would greatly appreciate all feedback positive and negative, and
> > > examples
> > > > of how a rule engine could be useful.  The examples I have so far
> are
> > > > derived from the jeops examples, and are a bit artificial for ejb:
> > they
> > > > compute factorials and fibonacci numbers.  They do serve as an
> > example
> > > of
> > > > essentially computing a transitive closure, not possible with
> simple
> > > > queries.
> > > >
> > > > This implementation is similar to database triggers, in that rule
> > > engine
> > > > interaction is not coded explicitly but triggered by calling an ejb
> > > method:
> > > > an interceptor detects the call and passes it to the rule engine.
> > > >
> > > > The implementation is fully transactional: all work (including
> > creating
> > > new
> > > > beans, etc) is done within the original transaction provided by the
> > > > original method call. ( A REQUIRES_NEW call in the middle of rule
> > > engine
> > > > work will get a separate rule engine instance, not interfering with
> > the
> > > > original transaction).
> > > >
> > > > Jeops is somewhat unusual among rule engines in that rather than
> > > operating
> > > > on tuples of values and interpreting rules, it operates on java
> > objects
> > > (in
> > > > this case remote interfaces) and compiles the rules into a java
> > class.
> > > >
> > > > The main problem I am aware of at this time is that the
> > implementation
> > > is
> > > > extremely slow.  This is only partly due to the very large amount
> of
> > > > logging information generated.  I have not yet investigated how to
> > > speed
> > > > things up.
> > > >
> > > > Please, try it out, tell me how it works, and what more is needed.
> > > >
> > > >
> > > > Thanks
> > > > David Jencks
> > > >
> > > >
> > > > _______________________________________________
> > > > Jboss-development mailing list
> > > > [EMAIL PROTECTED]
> > > > http://lists.sourceforge.net/lists/listinfo/jboss-development
> > > >
> > > 
> > > 
> > > _______________________________________________
> > > Jboss-development mailing list
> > > [EMAIL PROTECTED]
> > > http://lists.sourceforge.net/lists/listinfo/jboss-development
> > > 
> > 
> > 
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > http://lists.sourceforge.net/lists/listinfo/jboss-development
> > 
> 
> 
> _______________________________________________
> Jboss-development mailing list
> [EMAIL PROTECTED]
> http://lists.sourceforge.net/lists/listinfo/jboss-development
> 


_______________________________________________
Jboss-development mailing list
[EMAIL PROTECTED]
http://lists.sourceforge.net/lists/listinfo/jboss-development

Reply via email to