Hi,
Very mysterious. If I check the github repository as tagged for 4.2.0 I
can't see an addRule method in BasicForwardRuleInfGraph. Clearly I'm
missing something.
You can add rules to a reasoner but you would then have to rebuild the
InfGraph/InfModel.
Like I say, you can add backward rules to a running hybrid engine, if
that's any use but I don't believe there's any support for dynamically
adding forward rules.
Dave
On 03/04/2023 19:52, L B wrote:
Hi Dave,
Thanks for the update.
The Jena version I am using is 4.2.0.
image.png
Checked Jena version 4.5.0. This API seems gone.
The system we are developing may have thousands of rules. To make the
engine more efficient, we want some rules to be loaded/unloaded
dynamically. For example, the driving related rules are loaded when the
user is driving. When the user gets home, those driving rules will be
unloaded.
In Jena 4.5 API, the reasoner has addRules API, but I do not know how to
make it work.
//inf is the InfModel created already.
GenericRuleReasoner reasoner = (GenericRuleReasoner) inf.getReasoner();
reasoner.setMode(GenericRuleReasoner.HYBRID);
reasoner.setDerivationLogging(true);
reasoner.setTraceOn(true);
List<Rule> rules = Rule.parseRules(ruleStr);
reasoner.addRules(rules);
inf.prepare();
The rule added is never triggered. Is there any way we could add/remove
rules programmatically without cause to rebuild InfModal and recheck all
the existing rules?
Dave Reynolds <[email protected]
<mailto:[email protected]>> 于2023年3月30日周四 14:14写道：
There's no support for dynamically adding forward rules to a "running"
reasoner that I recall.
You can dynamically add backward rules to a hybrid reasoner, but that's
not relevant here.
Your code example suggests you are calling addRule on a
BasicForwardRuleInfGraph but, unless I'm missing something, that method
is not in the jena source. Is it something you have added?
You can add rules to a reasoner but then would essentially have to
build
a new InfGraph or reset the engine state of the current infgraph.
Either
way that's why you are seeing the original deduction retrigger.
If you need to fire some action when adding triples to a model, and
dynamically change the processing, I'd suggest using the listener
machinery rather than the rule system.
Dave
On 28/03/2023 18:43, L B wrote:
> I am currently still trying to figure out the solution.
>
> 1. If I do not call coreInfModel.prepare(), nothing happens
during the
> triple update which is WAD, I believe.
> 2. When one triple is updated, all the rules which have true
condition will
> be triggered, rather than the rules related. I am expecting the
other rules
> will not be triggered unless its related triplets are updated. Is it
> possible?
>
>
> L B <[email protected] <mailto:[email protected]>> 于2023年3
月24日周五 16:10写道：
>
>>
>> 1) Init code：
>>
>> GenericRuleReasoner reasoner = new GenericRuleReasoner(new
>> ArrayList<Rule>());
>> reasoner.setMode(GenericRuleReasoner.FORWARD);
>> mCoreInfModel = ModelFactory.createInfModel(reasoner,
>> mCoreModel);
>>
>> 2) Statement exits
>> （:A :B :C)
>>
>> 3) Rule exists and triggered before
>>
>> [ alwaysTrue:
>> (:A :B :C)
>> -> triggerAction
>> ]
>>
>> 4) Now, I am trying to add rules at runtime.
>>
>> [ rule2:
>> (:X :Y :Z)
>> -> triggerAction2
>> ]
>>
>> InfModel infModel = getCoreInfModel();
>> BasicForwardRuleInfGraph infGraph =
(BasicForwardRuleInfGraph)
>> infModel.getGraph(); infGraph.addRule(rule)
>> coreInfModel.prepare()
>>
>> 5) add triple (:X :Y :Z)
>>
>> val infGraph = infModel.graph as BasicForwardRuleInfGraph
>> infGraph.add(triple)
>>
>> *The problem comes, both "alwaysTrue" and "rule2" triggered.*
>>
>> *I am expecting only "rule2" is triggered. *
>>
>> Is there anyway that only "rule2" can be triggered since the updated
>> triple is only X, Y Z?
>>
>> Many thanks
>>
>>
>>
>
