Hello, I have many problems to integrate Drools in my existing Application that is running on JBoss AS 4.0.5 GA. When I try to load and execute the rule-file I get the following Exception: java.lang.RuntimeException: java.lang.NoSuchMethodError: org.eclipse.jdt.internal.compiler.CompilationResult.getProblems()[Lorg/eclip se/jdt/core/compiler/CategorizedProblem; javax.ejb.EJBException: java.lang.RuntimeException: java.lang.NoSuchMethodError: org.eclipse.jdt.internal.compiler.CompilationResult.getProblems()[Lorg/eclip se/jdt/core/compiler/CategorizedProblem; at org.jboss.ejb3.tx.Ejb3TxPolicy.handleExceptionInOurTx(Ejb3TxPolicy.java:69) at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:83) at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxInterceptor.java:191) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationIntercepto r.java:76) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.ejb3.stateless.StatelessInstanceInterceptor.invoke(StatelessInstan ceInterceptor.java:62) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.aspects.security.AuthenticationInterceptor.invoke(AuthenticationIn terceptor.java:77) at org.jboss.ejb3.security.Ejb3AuthenticationInterceptor.invoke(Ejb3Authenticat ionInterceptor.java:102) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagationInterceptor.ja va:47) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(AsynchronousInter ceptor.java:106) at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:10 1) at org.jboss.ejb3.stateless.StatelessContainer.dynamicInvoke(StatelessContainer .java:263) at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106) at org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invoke(AOPRemotingIn vocationHandler.java:82) at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:828) at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:681) at org.jboss.remoting.transport.socket.ServerThread.processInvocation(ServerThr ead.java:358) at org.jboss.remoting.transport.socket.ServerThread.dorun(ServerThread.java:412 ) My Application consists of the following parts: The rule-file: #created on: 04.09.2007 package drools.rules #list any import classes here. import drools.session.Message; #declare any global variables here rule "Hello World" when m : Message( status == Message.HELLO, message : message ) then System.out.println( message ); m.setMessage( "Goodbye cruel world" ); m.setStatus( Message.GOODBYE ); update( m ); end rule "GoodBye" no-loop true when m : Message( status == Message.GOODBYE, message : message ) then System.out.println( message ); m.setMessage( message ); end a Class to encapsulate the rule-initialisation and rule-execution (wrapper-Class): public class RuleEngineWrapper { private WorkingMemory workingMemory; private boolean debugMode = false; private DebugAgendaEventListener debugListener; public RuleEngineWrapper(WorkingMemory wm) { this.workingMemory = wm; debugListener = new DebugAgendaEventListener(); } /** * construct a RuleEngineWrapper with only a rule-file-name, no idea of * callers' class. Assume the rule file is located * * @param rulesFile */ public RuleEngineWrapper(String rulesFile) { this(RuleEngineWrapper.class, rulesFile); } /** * construct a RuleEngineWrapper with only a calling object known * * @param caller * @param rulesFile */ public RuleEngineWrapper(Object caller, String rulesFile) { this(caller.getClass(), rulesFile); } /** * construct a RuleEngineWrapper with Class caller and rule-file-name known. * We load the rule-file as classpath resource. * * @param caller * @param rulesFile */ public RuleEngineWrapper(Class caller, String rulesFile) { super(); try { final PackageBuilder builder = new PackageBuilder(); System.out.println(caller); builder.addPackageFromDrl(new InputStreamReader(caller .getResourceAsStream(rulesFile))); final RuleBase ruleBase = RuleBaseFactory.newRuleBase(); ruleBase.addPackage(builder.getPackage()); workingMemory = ruleBase.newStatefulSession(); debugListener = new DebugAgendaEventListener(); } catch (Exception e) { System.out.println("cannot read rule file: " + rulesFile); } } /** * Allow to add arbitrary objects as facts. Users can add any objects to * workingMemory * * @param o * the fact to be added */ public void addFact(Object o) { workingMemory.insert(o); } /** * Execute rules. * */ public void executeRules() { workingMemory.fireAllRules(); } /** * toggle debugging mode (adds a DebugAgendaEventListener if called once. * Removes if called again. */ public void setDebugMode( boolean debug ) { if (debugMode ) { workingMemory.removeEventListener( debugListener ); } else workingMemory.addEventListener(debugListener); } public WorkingMemory getWorkingMemory() { return workingMemory; } public void setWorkingMemory(WorkingMemory workingMemory) { this.workingMemory = workingMemory; } } A stateless Sessionbean for the access from the Testcase @Remote(droolsManagement.class) public @Stateless class droolsManagementBean implements droolsManagement { public void startRuleEngineWrapper(String rulesFile, ArrayList<Object> objektListe) throws Exception { try { //load up the rulebase + StatefulSession (WorkingMemory) RuleEngineWrapper rew = new RuleEngineWrapper("/drools/rules/" + rulesFile); for (Object object : objektListe) { rew.addFact(object); } rew.executeRules(); } catch (Exception e) { System.out.println("exception in 'droolsManagementBean.startRuleEngineWrapper(String, ArrayList<Object>)', cannot handle it..."); } } } And the test-case: @Test public void TestDroolsRuleEngineWrapper() { try { String rulesFile = "testRule.drl"; //go ! Message message = new Message(); message.setMessage( "Hello World" ); message.setStatus( Message.HELLO ); ArrayList<Object> objektListe = new ArrayList<Object>(); objektListe.add(message); droolsM.startRuleEngineWrapper(rulesFile, objektListe); } catch (Exception e) { System.out.println("Exception in TestDroolsRegeln.TestDroolsRuleEngineWrapper: " + e.getMessage()); e.printStackTrace(); } }