Drools Rule structure

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Hi i am new to Drools fusion and I have been developing some sample rules to understand working of drools fusion. I need some help in understanding drools
My rule:

rule "Sample Rule"

    when
     $t:Test (num == 10) from entry-point Stream
    then
        System.out.println($t.str);

end

Test is a class having a str String and num Integer.

I need event to be fired by some correlation such that it keep inserting test objects and fire event as num of those objects have sum more than 100 like: rule "Your First Rule"

    when
     $t:Test ($tmp:num) from entry-point Stream //store num's value

     ($tmp>100)      // fire if sum of num's more than 100
    then
        System.out.println($t.str);

end

My code is:

WorkingMemoryEntryPoint entryPoint1=ksession.getWorkingMemoryEntryPoint("Stream")
        def eg=new Test()
        eg.str="Test"
        eg.num=10
        EventFactHandle factHandle = (EventFactHandle)entryPoint1.insert(eg)

Ques 2: I want to understand the working of fireAllRules(). Do i need to trigger by this method everytime I insert an object into drools runtime(entrypoint or session).?

I hope you understand my situation.Please help and thanks in advance

1

There are 1 answers

1
laune On

I don't know what question #1 was supposed to be. I can see that the line

($tmp>100)

is syntactically incorrect; the condition should be part of the preceding pattern or enclosed in eval().

Question #2: You can insert any number of facts and call fireAllRules(), or you can call fireAllRules() after each insertion. Note, however, that the result may not be the same. Consider a scenario, where a rule removes a fact X() as soon as it triggers on a single X, and where another rule triggers as soon as there are two facts of type X(). The second rule may never fire if fireAllRules() is called after each insertion,