[rules-users] Collecting items in a List

[Wolfgang Laun]

Assuming that you call kSession.fireAllRules() only once after the insertion
of all facts, you have to select a single representative for all Alert facts
with identical case number.

Again assuming that the alertNo is unique, you can write

when
    Alert( $caseNumber : caseNumber, $alertNo: alertNo )
    not Alert( alertNo < $alertNo )
    $list : List( ) from collect($alertalert : Alert( caseNumber ==
$caseNumber))
then

-W

On 20/12/2012, devan.vanreenen at gmail.com <devan.vanreenen at gmail.com> wrote:
> Hi there,
>
> I have checked existing posts and able to find problems which are similar
> to
> mine but not exactly.
> I have an Alert object as per below, several alert instances may have the
> same caseNumber
> I am trying to collect all the Alert instances that have the same
> caseNumber, the rule is below, the rule below collects the items correctly
> but the execution happens for each Alert object inserted into the knowledge
> session. How can I get around this?
>
>
> public class Alert {
> 	
> 	
> 	int caseNumber;
> 	short alertNo;
> 	
> 	
> 	public int getCaseNumber() {
> 		return caseNumber;
> 	}
> 	public void setCaseNumber(int caseNumber) {
> 		this.caseNumber = caseNumber;
> 	}
> 	public short getAlertNo() {
> 		return alertNo;
> 	}
> 	public void setAlertNo(short alertNo) {
> 		this.alertNo = alertNo;
> 	}
> 	@Override
> 	public String toString() {
> 		return "Alert [caseNumber=" + caseNumber + ", alertNo=" + alertNo + "]";
> 	}
>
>
> }
>
> rule 'Collect Alerts for a specific case'
> dialect 'java'
> when
> 	Alert( $caseNumber : caseNumber)
> 	$list : List( ) from collect($alertalert : Alert( caseNumber ==
> $caseNumber))
> then
> 	for(Object a : $list){
> 		System.out.println(a);
> 	}
> end
>
>
> I insert 5 alert objects as per below
>
>
>             Alert alert1 = new Alert();
>             alert1.setAlertNo((short)1);
>             alert1.setCaseNumber(830826);
>
>             Alert alert4 = new Alert();
>             alert4.setAlertNo((short)4);
>             alert4.setCaseNumber(830826);
>
>             Alert alert7 = new Alert();
>             alert7.setAlertNo((short)7);
>             alert7.setCaseNumber(830826);
>
>             Alert alert3 = new Alert();
>             alert3.setAlertNo((short)3);
>             alert3.setCaseNumber(820424);
>
>             Alert alert5 = new Alert();
>             alert5.setAlertNo((short)5);
>             alert5.setCaseNumber(820424);
>
> I would like the output to be as follows
>
> Alert [caseNumber=820424, alertNo=3]
> Alert [caseNumber=820424, alertNo=5]
>
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=1]
>
> but instead the output is
>
> Alert [caseNumber=820424, alertNo=5]
> Alert [caseNumber=820424, alertNo=5]
> Alert [caseNumber=820424, alertNo=3]
> Alert [caseNumber=820424, alertNo=5]
> Alert [caseNumber=820424, alertNo=3]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=1]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=1]
> Alert [caseNumber=830826, alertNo=7]
> Alert [caseNumber=830826, alertNo=4]
> Alert [caseNumber=830826, alertNo=1]
>
>
>
>
>
> --
> View this message in context:
> http://drools.46999.n3.nabble.com/Collecting-items-in-a-List-tp4021256.html
> Sent from the Drools: User forum mailing list archive at Nabble.com.
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