Hi, I've a DRL file and Java Class, and ChangeSet.xml present in local drive D: DRL file is rulemaster.drl having rule A,rule B. My ChangeSet.xml is <change-set xmlns='http://drools.org/drools-5.0/change-set' xmlns:xs='http://www.w3.org/2001/XMLSchema-instance' xs:schemaLocation='http://drools.org/drools-5.0/change-set http://anonsvn.jboss.org/repos/labs/labs/jbossrules/trunk/drools-api/src/... <add <resource source='file:D:\rulemaster.drl' type='DRL' / </add</change-set Now My Java class is package com.sample; public class RuleEngine { private RuleEngine() { } public static final void main(String[] args) { int counter=0; try { System.out.println("Before rule engine start "); RuleEngine.start(); System.out.println("After rule engine start "); do{ Collection<KnowledgePackage> kpackages = _kbase.getKnowledgePackages(); System.out.println("no of packages"+kpackages.size()); for(KnowledgePackage kpackage : kpackages) { for(org.drools.definition.rule.Rule rule1 :kpackage.getRules()) { String packname= rule1.getPackageName(); String rulename=rule1.getName(); System.out.println("This is : "+packname+" Packages and RuleName is " +rulename); } } counter++; try{ Thread.sleep(10000); }catch (InterruptedException e){ System.out.println("Sleep exception occured"); } }while(counter < 10000); }catch (Throwable t){ t.printStackTrace(); } } public static synchronized RuleEngine start() { try{ if ( _instance == null) { _instance = new RuleEngine(); //create knowledgeBuilder String url="file:D:\\ChangeSet.xml"; _kagent = KnowledgeAgentFactory.newKnowledgeAgent( "MyAgent" ); System.out.println("after creating kagent"); _kagent.applyChangeSet(ResourceFactory.newUrlResource(url)); System.out.println("after apply change set"); //Create Knowledge Base _kbase = _kagent.getKnowledgeBase(); ResourceChangeScannerConfiguration sconf= ResourceFactory.getResourceChangeScannerService().newResourceChangeScannerConfiguration(); sconf.setProperty("drools.resource.scanner.interval", "5"); ResourceFactory.getResourceChangeScannerService().configure(sconf); ResourceFactory.getResourceChangeNotifierService().start(); ResourceFactory.getResourceChangeScannerService().start(); System.out.println("After starting Notification service"); } }catch(Exception e) { System.out.println(e.getMessage()); } return _instance; } private static KnowledgeAgent _kagent; private static RuleEngine _instance; private static KnowledgeBase _kbase=null; private static StatelessKnowledgeSession _ksession=null; } Now as I'm making changes to DRL file by adding Rule C,Rule D..I've written applyChangeSet method in Java class.But it is not displaying new RuleNames.Please suggest me what is the way to applyChangeSet to DRL file.Does anythng went wrong in above code.. Please suggest me THanks -- View this message in context: http://drools.46999.n3.nabble.com/Unable-to-apply-ChangeSet-to-DRL-file-t... Sent from the Drools: User forum mailing list archive at Nabble.com.