RE: [rules-users] Help on using Drools with embedded objects

There were a couple of ways mentioned in the Drools documentation for 4.0.7. 1) Eval is the Quick way to get this done. This does have a performance penalty though 2) Read up on using the -> operator that allowed you to go deeper into the object hierarchy. 3) A third way which I used was to write setter and getter methods for fields I needed in the rules condition in the root class itself. Since Drools introspects on setters and getters this seemed to work. To take an example, if I have a class as follows:- Class B{ int a; public int geta() {}; public int seta() {}; } Class A { B b; public int getA() { Return this.b.geta(); } Public void seta(int b) { this.b.seta(b); } } From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Divya Rajendranath Sent: Monday, February 23, 2009 2:57 PM To: rules-users(a)lists.jboss.org Subject: [rules-users] Help on using Drools with embedded objects Hi, I am planning to use Drools - JBoss Rules Engine. My requirement is to disburse mails from my application to different groups based on various criteria. I want to use Drools here. My object structure is as follows: class A{ String B = ""; B b; C c; } Hence Obj A has embedded objects within it, and obj B and C further has embedded objects. class B { String X; Z z; } class Z{ String t; String s; } The decision on sending the mails based on the fields in embedded objects of A. I pass instance of A to Drools Format of drl file: package...; import ..; rule "Test" when $a:A(B(Z(s == "testvalue"))) then $a.setSomething(); update($a); end I wanted to know if this (accessing fields in embedded/child object) is feasible with Drools. I get an error saying "UNable to compile myfile.drl when i try to fo this. Could some one look into this issue and let me know the reason for this ? Thanks -D MASTEK LTD. Mastek is in NASSCOM's 'India Top 20' Software Service Exporters List. In the US, we're called MAJESCOMASTEK ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Opinions expressed in this e-mail are those of the individual and not that of Mastek Limited, unless specifically indicated to that effect. Mastek Limited does not accept any responsibility or liability for it. This e-mail and attachments (if any) transmitted with it are confidential and/or privileged and solely for the use of the intended person or entity to which it is addressed. Any review, re-transmission, dissemination or other use of or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. This e-mail and its attachments have been scanned for the presence of computer viruses. It is the responsibility of the recipient to run the virus check on e-mails and attachments before opening them. If you have received this e-mail in error, kindly delete this e-mail from desktop and server. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~