The problem here is a different one. The engine is calling shutdown() on a thread pool and even without any task being executed, the thread is blocked in an internal JDK queue waiting for the timeout. I replaced the call by shutdownNow(), forcing the jdk to signal an interrupt to the thread and this seemed to work. I am investigating side effects of this procedure right now. []s Edson 2009/7/16 Mark Proctor <mproctor(a)codehaus.org&gt; -- Edson Tirelli JBoss Drools Core Development JBoss by Red Hat @ www.jboss.com

Rafael, It is the JDK class: Class ScheduledThreadPoolExecutor Check the API for methods shutdown() and shutdownNow(). I am also looking at the JDK source code. It seems safe in our case to change the call to shutdownNow() instead of the previous call to shutdown(). The shutdown is called on session dispose() only and as so it is an irreversible operation anyway. I am just double checking, but I think there is no choice. Brian Goetz's Java Concurrency in Practice also states that the jdk blocking operations may or may not be canceled gracefully (case-by-case) on chapter 7. Give me another hour to make sure everything is ok and I will commit a fix. https://jira.jboss.org/jira/browse/JBRULES-2211 []s Edson 2009/7/17 Rafael Ribeiro <rafaelri(a)gmail.com&gt; -- Edson Tirelli JBoss Drools Core Development JBoss by Red Hat @ www.jboss.com

Hi Edson! as I've already mentioned I've modified the sample so, if you get the StockTick sample and replace the Main class this will run fine. The sample shuts down fine but as I saw it sets the JFrame uses frame.setDefaultCloseOperation( WindowConstants.EXIT_ON_CLOSE ); which in turn makes the trick. Below the code of my modified main class: package org.drools.examples.broker; import org.drools.KnowledgeBase; import org.drools.KnowledgeBaseConfiguration; import org.drools.KnowledgeBaseFactory; import org.drools.builder.KnowledgeBuilder; import org.drools.builder.KnowledgeBuilderFactory; import org.drools.builder.ResourceType; import org.drools.conf.EventProcessingOption; import org.drools.examples.broker.model.Company; import org.drools.examples.broker.model.CompanyRegistry; import org.drools.examples.broker.model.StockTick; import org.drools.io.ResourceFactory; import org.drools.runtime.StatefulKnowledgeSession; import org.drools.runtime.rule.WorkingMemoryEntryPoint; public class Main { private static final String RULES_FILE = "/broker.drl"; static StatefulKnowledgeSession session; static WorkingMemoryEntryPoint tickStream; /** * @param args */ public static void main(String[] args) throws Exception { // set up and show main window CompanyRegistry companies = new CompanyRegistry(); KnowledgeBuilder builder = KnowledgeBuilderFactory.newKnowledgeBuilder(); try { builder.add( ResourceFactory.newInputStreamResource( Main.class.getResourceAsStream( RULES_FILE ) ), ResourceType.DRL); } catch ( Exception e ) { e.printStackTrace(); } if( builder.hasErrors() ) { System.err.println(builder.getErrors()); System.exit( 0 ); } KnowledgeBaseConfiguration conf = KnowledgeBaseFactory.newKnowledgeBaseConfiguration(); conf.setOption( EventProcessingOption.STREAM ); KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase( conf ); kbase.addKnowledgePackages( builder.getKnowledgePackages() ); session = kbase.newStatefulKnowledgeSession(); session.setGlobal( "services", new BrokerServices() { public void log(String message) { System.out.println(message); } }); for( Company company : companies.getCompanies() ) { session.insert( company ); } session.fireAllRules(); tickStream = session.getWorkingMemoryEntryPoint( "StockTick stream" ); for (int i=10;i>0;i--) { tickStream.insert(new StockTick("RHT", i*10, System.currentTimeMillis())); session.getAgenda().getAgendaGroup( "evaluation" ).setFocus(); session.fireAllRules(); } session.dispose(); session.halt(); System.out.println("Still running..."); } } regards, Rafael Ribeiro 2009/7/16 Edson Tirelli <tirelli(a)post.com&gt;