[rules-users] Rules Engine always running
Jones, Alan R
alan.r.jones at boeing.com
Wed Mar 28 14:25:39 EDT 2007
Thanks for your help!
aj
--------------------------------------------
Alan R Jones
Boeing S&IS Mission Systems
Denver Engineering Center (BDEC)
303.307.3415
________________________________
From: Edson Tirelli [mailto:tirelli at post.com]
Sent: Wednesday, March 28, 2007 12:21 PM
To: Rules Users List
Subject: Re: [rules-users] Rules Engine always running
Yes, that is standard approach.
Just don't share the same working memory among multiple threads
(seems you are not doing that, so just reinforcing). The rule base may
be shared, no problem.
[]s
Edson
2007/3/28, Jones, Alan R <alan.r.jones at boeing.com>:
This is actually very close to the approach I am going to try:
The caching is replaced by an object representing/encapsulating
a given rulebase created as a new/separate thread. A reference to said
object is registered (cached?). When a Fact comes along, the appropriate
rulebase/object is looked up and the fact is fed to it (the object has a
method that takes the fact and asserts it into a new working memory),
then the object fires the rule. Does this approach make sense?
Thanks,
aj
________________________________
From: Edson Tirelli [mailto:tirelli at post.com]
Sent: Wednesday, March 28, 2007 11:03 AM
To: Rules Users List
Subject: Re: [rules-users] Rules Engine always running
Alan,
If you have different sets of rules that you want to apply in
different circunstances, you can compile and cache each of this sets as
a rulebase (note that the set may contain a single rule).
Then, for each fact that arrives, you decide which is the
rulebase that applies to it, create a working memory for that rulebase,
assert the fact, run the rule and throw the working memory away (as, you
mentioned you don't want this working memory anymore).
You can, of course, work with a single rulebase and keep
adding and removing rules from it, but it will be more expensive to
handle that for the use case you described.
If you are able to detail your use case, we may be able to
help you more.
Regards,
Edson
2007/3/28, Jones, Alan R <alan.r.jones at boeing.com>:
Yes, some of these things are being considered. Thanks
for your input , it has been helpful!
aj
________________________________
From: Anstis, Michael (M.) [mailto:manstis1 at ford.com]
Sent: Wednesday, March 28, 2007 9:12 AM
To: Rules Users List
Subject: RE: [rules-users] Rules Engine always running
I assume rules are dynamically added to the Rulebase and
that there is not a static set of rules associated with each application
release?
I believe new rules can be dynamically added to the
existing Rulebase - whether existing WM's inherit the new rules I don't
know. Agenda Groups could provide the control of which groups of rules
fire.
Also, if you retain FactHandles to all asserted Facts
depending upon the decision made by the component the legacy Facts can
be retracted before the new rule is activated.
I assume you'll also have some "Rule life-cycle" control
in place? Either removing rules from a Rulebase (I believe to be
possible) or destroying redundant WM's (as per your proposal).
Sorry, this doesn't add much more value - although input
from more experienced users is welcomed.
Cheers,
Mike
________________________________
From: rules-users-bounces at lists.jboss.org
[mailto: rules-users-bounces at lists.jboss.org
<mailto:rules-users-bounces at lists.jboss.org> ] On Behalf Of Jones, Alan
R
Sent: 28 March 2007 15:29
To: Rules Users List
Subject: RE: [rules-users] Rules Engine always
running
Mike,
Thanks for you rresponse, however I'm not sure
based on what we are wanting to do that we should use a single working
memory. The proposed approach is:
a rule has been added to the rule base, then a
Fact (object) comes along and we instantiate a working memory and fire
all rules relative to this working memory. The outcome from Drools is
evaluated by another sw component, and it is decided to try a different
rule with a given Fact.
So, a new rule, rule #2, comes along with
slightly different specifics on what it is supposed to match, so it is
added to the rule base. Then, Fact #2 comes down the pipeline. A new
working memory #2 is instantiated against the existing rulebase, Fact #2
is asserted, and fireAllRules() called against the working memory #2.
The desired behavior is that only rule #2 is
actually kicked into action (against Fact #2), since the first rule and
fact is done with. We don't want the previous rules/facts in the rule
base operating any longer.
Maybe I just don't know enough about the proper
application of rules when solving particular problems to ask the right
questions -- my task is to expose JBoss rules as a service so I'm trying
to understand a bit about it's operation.
Thanks,
aj
--------------------------------------------
Alan R Jones
Boeing S&IS Mission Systems
Denver Engineering Center (BDEC)
303.307.3415
________________________________
From: Anstis, Michael (M.)
[mailto:manstis1 at ford.com]
Sent: Wednesday, March 28, 2007 2:23 AM
To: Rules Users List
Subject: RE: [rules-users] Rules Engine always
running
Hi Alan,
A working memory is in essence always
available\running whilst there is a reference to it; other than the
"main" thread (on which your public static void main executes) you don't
need to use other threads (but this obviously depends upon what exactly
you're trying to achieve). The Rulebase can contain all of your
production rules (in fact this is probably the recommended approach as,
assuming some rules share a common pattern, the resulting RETE network
will be optimised); and you can feed incoming objects (Facts in JBoss
Rules terms) into one working memory created from the one Rulebase. As
objects are asserted patterns (LHS) defining the rules are matched and,
once fully matched, rules are activated for execution (RHS).
Unfortunately I don't have any experience of JBoss Rules in a
multi-threaded environment.
For example:-
public static void main(String args[]) {
Rulebase rb = loadRuleBase();
WorkingMemory wm =
rb.newWorkingMemory();
while (!exit()) {
Collection c =
getObjectsFromWherever();
assertObjectsIntoWorkingMemory(c, wm);
wm.fireAllRules();
try {
Thread.sleep(1000);
}
catch(InterruptedException ie) {
}
}
}
With kind regards,
Mike
________________________________
From:
rules-users-bounces at lists.jboss.org [mailto:
rules-users-bounces at lists.jboss.org] On Behalf Of Jones, Alan R
Sent: 27 March 2007 19:05
To: Rules Users List
Subject: [rules-users] Rules Engine
always running
Kind of new to JBoss Rules...I'm trying
to fiigure out from what i have read so far if the following scenario is
possible:
1. Start up an instance of a working
memory (say, with dummy rule?) and keep it running, feeding it data
objects to operate on from time to time.
2. As needed, kick off as many instance
of working memory within the single rule base (in a separate thread) and
keep them going as in step 1
The idea is to keep the rules engine
running constantly, but kick off separate working-memory threads for the
injection of various incoming rule sets and the objects those rule sets
work on as needed. Can anyone provide some insight to this? Pointers to
examples, perhaps?
Alan J.
_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3124-6000
Mobile: +55 11 9218-4151
JBoss, a division of Red Hat @ www.jboss.com
_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3124-6000
Mobile: +55 11 9218-4151
JBoss, a division of Red Hat @ www.jboss.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20070328/5e059fe3/attachment.html
More information about the rules-users
mailing list