2:58 a.m.
Hi here is the same thing converted to mvl
// this Bundler.java has integer member that keeps incrementing
global Bundler bundler
rule "Apply 10% discount if you purchase 2 items"
when
$s1 : CartItem( *productId == 219759*, processed == false)
$s2 : CartItem( this != $s1, productId == $s1.productId, processed
== false)
$m : RuleMessage()
then
$m.addMessage("Found item1: " + $s1.getName() + " id:
"+$s1.getId());
$m.addMessage("Found item2: " + $s2.getName() + " id:
"+$s2.getId());
modify($s1){
setProcessed(true),
setPromoItemDiscount($s1.getPrice() * 0.1),
setPromoId("1"),
setBundleId(bundler.getId()),
setAggrigatorId(1)
};
modify($s2){
setProcessed(true),
setPromoItemDiscount($s2.getPrice() * 0.1),
setPromoId("1"),
setBundleId(bundler.getId()),
setAggrigatorId(1)
};
$m.addMessage("bundled ["+*bundler.getId()*+"]
"+$s1.getId()+","+$s2.getId());
bundler.increment();
end
the above rule dosent fire, but if I change the highlighter to
getProductId() == 219759, or use productId == "219759", may be this is some
edge case but it took long time for me to figure it out productId is String.
now consider the *bundler.getId()*, if I use *bundler.id* I get compilation
error.
Rule Compilation error : [Rule name='Apply 10% discount if you purchase 2
items']
com/example/promotions/promotionEngine/Rule_Apply_10__discount_if_you_purchase_2_items_0.java
(23:1592) : The field Bundler.id is not visible
2011-09-09 13:18:39,863 INFO [STDOUT] - 2011-09-09 13:18:39,863 INFO
[PromotionsManager] - ksession initialized
2011-09-09 13:18:39,863 INFO [STDOUT] - 2011-09-09 13:18:39,863 INFO
[PromotionsManager] - Exploding items and inserting cart
2011-09-09 13:18:39,864 INFO [STDOUT] - 2011-09-09 13:18:39,863 ERROR
[CheckOutBasedUtilities] - Failed to apply promo offers
java.lang.RuntimeException: Unexpected global [bundler]
at
org.drools.common.AbstractWorkingMemory.setGlobal(AbstractWorkingMemory.java:613)
at
org.drools.impl.StatefulKnowledgeSessionImpl.setGlobal(StatefulKnowledgeSessionImpl.java:332)
at
com.example.promotions.promotionEngine.PromotionsManager.applyOffers(PromotionsManager.java:154)
at
com.example.promotions.promotionEngine.PromotionsManager.shuffleForOffers(PromotionsManager.java:61)`
lastly my actual problem that I am looking for a solution lets say we have
"Buy X items of A and get Y Items of B". X=5 & Y=4 from the original
problem
I want to template the rule and load the values of X,A,Y,B from database or
excel etc. if I use modify the error is as follows
*my rule*
rule "Buy X units of Product A and Get Y units of Product B Free"
when
$itemsX : ArrayList( size == 2 ) from collect( CartItem(
getProductId() == 24257, !isProcessed()))
$itemsY : ArrayList( size == 1) from collect(CartItem(
getProductId() == 24260, !isProcessed()))
$m : RuleMessage()
then
for(Object item : $itemsX){
CartItem ci = (CartItem) item;
$m.addMessage( ci.getId()+")Found item: "+ci.getItemId()+"
name: "+ci.getName());
modify(ci){
setProcessed(true),
setPromoItemDiscount(0),
setPromoId("2"),
setBundleId(bundler.getId()),
setAggrigatorId(1)
};
}
for(Object item : $itemsY){
CartItem ci = (CartItem) item;
$m.addMessage( ci.getId()+")Found item: "+ci.getItemId()+"
name: "+ci.getName());
modify(ci){
setProcessed(true),
setPromoItemDiscount(ci.getPrice()),
setPromoId("2"),
setBundleId(bundler.getId()),
setAggrigatorId(2)
};
}
bundler.increment();
end
Rule Compilation error : [Rule name='Buy X units of Product A and Get Y
units of Product B Free']
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(11:1236) : The method setProcessed(boolean) is undefined for the type
Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(12:1265) : The method setPromoItemDiscount(int) is undefined for the type
Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(13:1299) : The method setPromoId(String) is undefined for the type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(14:1325) : The method setBundleId(Integer) is undefined for the type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(15:1364) : The method setAggrigatorId(int) is undefined for the type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(22:1702) : The method setProcessed(boolean) is undefined for the type
Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(23:1731) : The method setPromoItemDiscount(Double) is undefined for the
type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(24:1777) : The method setPromoId(String) is undefined for the type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(25:1803) : The method setBundleId(Integer) is undefined for the type Object
com/example/promotions/promotionEngine/Rule_Buy_X_units_of_Product_A_and_Get_Y_units_of_Product_B_Free_0.java
(26:1842) : The method setAggrigatorId(int) is undefined for the type Object
Rule Compilation error : [Rule name='Apply 10% discount if you purchase 2
items']
com/example/promotions/promotionEngine/Rule_Apply_10__discount_if_you_purchase_2_items_0.java
(23:1592) : The field Bundler.id is not visible
On Fri, Sep 9, 2011 at 12:40 PM, Sandeep Bandela <gibsosmat(a)gmail.com>wrote:
Hi Wolfgang,
This is what I did initially but for product > 2 I didnt find a generic way
to do this. following is my first rule. I didnt use field names because it
was giving error that member is not accessible. I will attach the errors of
each case in a few mins.
rule "Apply 10% discount if you purchase 2 items"
dialect "java"
when
$s1 : CartItem( getProductId() == 236061, !isProcessed())
$s2 : CartItem( getProductId() == 236061, getId() != $s1.getId(),
!isProcessed())
$m : RuleMessage()
then
$m.addMessage("Found item1: " + $s1.getName() + " id:
"+$s1.getId());
$m.addMessage("Found item2: " + $s2.getName() + " id:
"+$s2.getId());
modify($s1){
setProcessed(true),
setPromoItemDiscount($s1.getPrice() * 0.1),
setPromoId("1"),
setBundleId(bundler.getId()),
setAggrigatorId(1)
};
modify($s2){
setProcessed(true),
setPromoItemDiscount($s2.getPrice() * 0.1),
setPromoId("1"),
setBundleId(bundler.getId()),
setAggrigatorId(1)
};
bundler.increment();
end
2011/9/9 Wolfgang Laun <wolfgang.laun(a)gmail.com>
> Your rule exhibits procedural thinking. (For an aspiring rule programmer
> his is typical teething troubles.)
>
> There's no need to collect all A's and B's in order to determine their
> number being greater than one or two - this is achieved automatically by a
> simple triple match rule. Consider
>
> rule "2A - 1B"
> when
> $a1: CartItem( productId == "A", processed == false )
> $a2: CartItem( this != $a1, productId == "A", processed == false )
> $b: CartItem( productId == "B", processed == false )
> then
> modify( $a1 ){...}
> modify( $a2 ){...}
> modify( $b ){...}
> end
>
> Note:
>
> - The modify is essential. (When you say "doesn't work", always
> provide details.)
> - Use the field name rather than the getter call - it improves
> readability.
> - I'm not sure whether 5.2.0 final handles boolean fields correctly -
> IIRC, there were some issues. It's possible that CartItem(..., !processed)
> works.
>
> -W
>
> 2011/9/8 Sandeep Bandela <gibsosmat(a)gmail.com>
>
>> Hi,
>> I am new to rules engine, after going through the examples shipped
>> (shopping.drl, petstore.drl)
>> I am trying to implement promotional discounting using drools 5.2.0
>> final, stateful session. assume cart has all the items that customer wants
>> to buy,
>> I am trying to bundle them together with the existing offers
>>
>> rule "Buy X units of Product A and Get Y units of Product B Free"
>> dialect "java"
>> when
>> $itemsA : ArrayList( size >= 2) from collect( CartItem(
>> getProductId() == "A", !isProcessed()))
>> $itemsB : ArrayList( size >= 1) from collect( CartItem(
>> getProductId() == "B", !isProcessed()))
>> then
>> // current scenario buy 2*A and get 1*B
>> int x = 2;
>> int y = 1;
>> for(int i=0 ; i < x ; i++){
>> CartItem $ci = (CartItem) $itemsA.get(i);
>> // modify($ci){setProcessed(true) ... } dosent work
>> $ci.setProcessed(true);
>> $ci.setItemDiscount(0.0);
>> $ci.setBundleId(bundler.getId());
>> }
>>
>> for(int i=0 ; i < y ; i++){
>> CartItem $ci = (CartItem) $itemsB.get(i);
>> $ci.setProcessed(true);
>> $ci.setItemDiscount($ci.getPrice());
>> $ci.setBundleId(bundler.getId());
>> }
>> // global counter to identify bundled items
>> bundler.increment();
>> end
>>
>> the above rule calculates only for 1 set of offer i.e first 2*A & 1*B are
>> considered, rest in the cart are not bundled.
>> if customer buys 4*A + 2*B it dosent consider it. am I missing anything?
>> is this the right way to do it?
>> any feedback is appreciated.
>>
>>
>>
>>
>> --
>> Regards,
>> Sandeep Bandela.
>>
>>
>> _______________________________________________
>> rules-users mailing list
>> rules-users(a)lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>>
>
> _______________________________________________
> rules-users mailing list
> rules-users(a)lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>
--
Regards,
Sandeep Bandela.
--
Regards,
Sandeep Bandela.