I have an Object in working memory. This object has an ArrayList of Integer objects. I am trying to create a rule that will count all occurrences of Integers in this ArrayList that are non-zero and then calculate the sum of all the Integers in the ArrayList and then check the total against a range. I understand how to count the non-zero occurrences but I am at a complete loss as to how to calculate the sum of the Integer objects in the ArrayList. Here is the rule I have thus far rule "Rule 1" dialect "java" when $mo : MyObject( ) $i : ArrayList ( ) from collect ( Number( intValue > 0 ) from $mo.getNumbers() ) $total : Number( ) from accumulate ??? then System.out.println("Rule 1: i.size() = " + $i.size()); System.out.println("Rule 1: total = " + $total); end I have been unsuccessful in finding a post that deals with how to fill in the ??? portion of my rule. My apologies in advance if I happen to miss such a post. Any help is greatly appreciated. Regards, Gerald -- View this message in context: http://www.nabble.com/accumulate---sum-and-ArrayList-tp16033216p16033216.... Sent from the drools - user mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users