Drools 5.1.1意外的累积和收集行为

Question

I'm using Spring AMQP to read messages from RabbitMQ. After a message is read it's deserialized into one header (parent) object and multiple detail (child) objects. Those facts are then inserted into a Drools stateless rule session. Finally, the updated facts are inserted into a database.

I have several rules that will aggregate the detail facts using either the collect or accumulate functions. Here's an example.

rule "Header.TotalDuration" 
when 
    h : BresHeader() 
    n : Number() 
            from accumulate( d : BresDetail(willSendToInvoice==true, 
                                            uniqueConfID ==   h.uniqueConfID),
                             sum(d.Duration) ) 
then 
    h.TotalDuration = new Integer(n.longValue()); 
    System.out.println("[TotalDuration] rule ran"); 
end 

If I run this once (reading in one message) in jUnit, the TotalDuration is calculated correctly. If I run it in tomcat (continuously reading messages) the values for TotalDuration are not correct and increase after each each pass (message is grabbed, rules ran, facts persisted, repeat) and I can't figure out why.

Can anyone shed light on this behavior?

Answer 1

也许您有一个static变量，可以将事实从以前的消息继续传递到新消息。