Re: [rules-users] rules for promotional offers

If the declared type of productId and getProductId() is String, it should be compared to a string literal. (A conversion might be made, but don't rely on that.) You cannot access components of a global in RHS code using the simplified notation (not unless you use "mvel" - but don't do that.) Here, all accesses should be written the usual Java way, with getter and setter calls. The problem you have with modify(ci) is a bug (fixed for 5.3.0). As a workaround,use modify( (CartItem)ci ){ ... } -W 2011/9/9 Sandeep Bandela <gibsosmat(a)gmail.com&gt; > some more info for the modify() problem, the CartItem is an interface and > the implementation is CartItemImpl. if this info leads to some clues. > > > On Fri, Sep 9, 2011 at 1:28 PM, Sandeep Bandela <gibsosmat(a)gmail.com&gt;wrote: > >> 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&gt;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&gt; >>> >>>> 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&gt; >>>> >>>>> 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. >> >> > > > -- > 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