Thanks for your quick reply... AddressType is Enum and have around 15 odd values, based on the taxpayer type some of the AddressTypes would be selected... Addresses is list of Address and addressType is one of the field under Address. All the addresses may be of same or different types (say a taxpayer can have two houses ) -- View this message in context: http://drools.46999.n3.nabble.com/All-the-values-from-one-list-must-be-pr... Sent from the Drools: User forum mailing list archive at Nabble.com.

Thanks laune!!! I think I did not explain properly and duplicate name "FOREIGN_BUSINESS" added more to the confusion... still you understood my problem , I will try putting more flesh on the bones in terms of classes to explain further details... public class TaxPayer { ... ArrayList<Address> addersses; TaxpayerType taxpayerType; ... } public class Address { ... AddressType addressType; ... } public enum AddressType{ UNKNOWN, BUSINESS, FOREIGN_BUSINESS_ADDRESS, RENTED, OWNED, .... } public enum TaxpayerType{ BUSINESS, FOREIGN_BUSINESS, INDIVIDUAL, FAMILY, PROPRITER .... } Now based on the taxpayerType say FOREIGN_BUSINESS, the taxpayer must have atleast 2 Addresses (BUSINESS and FOREIGN_BUSINESS_ADDRESS). I will have seperate rule for each type of tax payer, I am not passing in the AddressTypes (BUSINESS and FOREIGN_BUSINESS_ADDRESS) to be verified against as the facts, I want to set these values in the rule. So ideally I want something like rule "Validate Foreign Business" when $tpType: List() from [ AddressType.BUSINESS, AddressType.FOREIGN_BUSINESS_ADDRESS ] //This line is incorrect Taxpayer( $name: name, taxpayerType == $tpType, $addrs: addresses ) accumulate( Address( $addrType: addressType ) from $addrs, $addrTypeSet: collectSet( $addrType ) ) eval( ! $addrTypeSet.containsAll( $addressTypes ) ) then System.out.println( $name + " is not OK" ); end Also is it possible to show which address type is missing? say AddressType.BUSINESS is not present in the list thanks in advance for your help the rule is always resolving to success irrespective of weather the addresses are present or not. the only change that I have done is replaced $tpType: TaxpayerType( $addressTypes: addressTypes ) with $tpType: -- View this message in context: http://drools.46999.n3.nabble.com/All-the-values-from-one-list-must-be-pr... Sent from the Drools: User forum mailing list archive at Nabble.com.

Thanks, I am following your steps. -- View this message in context: http://drools.46999.n3.nabble.com/All-the-values-from-one-list-must-be-pr... Sent from the Drools: User forum mailing list archive at Nabble.com.