[rules-dev] Possible Bug: Nodes of inherited types with drools.getActivation().remove()

[Arjun Dhar]

>     So, may I suggest you open a JIRA with your example for us to investigate 
the bug? Also, I'm tempted to refactor the interface if possible to not expose 
the method remove() in the consequence...    What removes does is to remove the 
activation from the agenda, but the activation already fired, so what's the 
point of removing it? It may be the case that this is also creating an 
inconsistent state in the engine, so we need to check if that's the case and 
not expose the method anymore...
>     Also, maybe you can show us a more complete example of what you are 
trying to achieve, so we can advise you on how to do it without calling the 
activation remove() method.    Thank you for reporting!    Regards,       Edson

Hi Edson,
 For a large number of rules comming from decison tables, when arranging them 
sometimes it is helpful to modularize tables; with the result of one rule-table 
driving another rule table. The preferred method is Decision table. Also this 
allows a person to lazy load rules over a set of base rules (part of the reason 
is business process and stability around an established concept. The format 
makes sense accoring to the business model also) <-- Background, so now i'll 
get to the point!

So there is a need of one set of rules (outcome) to influence another (using 
tables). Scenario is like this:

Table 1:
-----------
Rule 1.1
Rule 1.2.
Rule 1.3.


Table 2:
----------
Rule 1.2.1 (If fires will influence 1.2)
Rule 1.2.2 (If fires will influence 1.2)

>From this point on, you could suggest anything you see is not fit <----

... Thre preferred way to influence the connection = Change an attribute of the 
same object (Since the specific rule in the top table cannot fire till its 
conditions are not fullfilled); so when the attribute is set then only the 
rules in the above table will become active for that object.

So when the "Business Object" is modified in Table 2, and hence modify() is 
called.

You are right, the activation fires and is removed but due to modify() it 
causes a re-firing and puts some already fired activation back in the Agenda.

Initally it hung, I realized the reason and put "no-loop". That stopped the 
recursion but I noticed certain activationse firing multiple times (Ideally I'd 
like the activation to fire and get out but here it would add it back again)
which is not acceptable.

I used "drools.getActivation().remove()" and it stopped the repeats, but then 
it was removing subsequent activations as well. I know why now. What I want to 
do is prevent this rule from firing again but inturn remove is removing the 
next activation. So the question is how to prevent the activation for that 
object not to fire again????

My problem ends here (I understand it better now, not sure it should go into 
JIRA yet. Would like your comments one more time)

About your comment about removing it. Due to the declrative nature of rules 
there are lot of conceptual barriers. So conceptual workarounds are restricted 
by the technology so we need every advantage. But then again, if you show me a 
better path to a solution I'd be more than happy.

Thanks Edson, Appreciate it!