Sorry!!! I forgot to mention I'm using Eclipse 3.5 (Galileo) in Windows XP. I even wonder if it would be better to use Ganymede instead, as it's known JBoss Tools in general work better with this Eclipse version, for JBoss Tools' stable version. ANA FLÁVIA FONSECA DOS SANTOS Analista de Desenvolvimento de Software PST Eletrônica S/A Phone: +55 19 3787 6379 aflavia(a)pst.com.br www.pst.com.br www.positron.com.br ----- Forwarded by Ana F Santos/Pst on 14/09/2009 09:43 ----- From: Ana F Santos/Pst To: rules-users(a)lists.jboss.org Date: 14/09/2009 09:40 Subject: java.lang.NoSuchMethodError on every Action node Hi everyone. I've been trying to use Drools for the past month, and sometimes I have problems I can't guess anymore how to solve. This time, every action I try to insert in a ruleflow, I receive a java.lang.NoSuchMethodError. I'm even trying a really simple ruleflow with just one simple action - like System.out.println("Test"); - and all I get is a java.lang.NoSuchMethodError. [ The stack trace: java.lang.NoSuchMethodError: br.com.pst.packages.ruleflows.Process_br_com_pst_packages_ruleflows_0.action0(Lorg/drools/spi/KnowledgeHelper;Lorg/drools/spi/ProcessContext;)V at br.com.pst.packages.ruleflows.Process_br_com_pst_packages_ruleflows_0Action0Invoker.execute( Process_br_com_pst_packages_ruleflows_0Action0Invoker.java:20) at org.drools.workflow.instance.node.ActionNodeInstance.internalTrigger( ActionNodeInstance.java:54) at org.drools.workflow.instance.impl.NodeInstanceImpl.trigger( NodeInstanceImpl.java:111) at org.drools.workflow.instance.impl.NodeInstanceImpl.triggerConnection( NodeInstanceImpl.java:142) at org.drools.workflow.instance.impl.NodeInstanceImpl.triggerCompleted( NodeInstanceImpl.java:128) at org.drools.workflow.instance.node.StartNodeInstance.triggerCompleted( StartNodeInstance.java:49) at org.drools.workflow.instance.node.StartNodeInstance.internalTrigger( StartNodeInstance.java:41) at org.drools.workflow.instance.impl.NodeInstanceImpl.trigger( NodeInstanceImpl.java:111) at org.drools.ruleflow.instance.RuleFlowProcessInstance.internalStart( RuleFlowProcessInstance.java:16) at org.drools.process.instance.impl.ProcessInstanceImpl.start( ProcessInstanceImpl.java:185) at org.drools.workflow.instance.impl.WorkflowProcessInstanceImpl.start( WorkflowProcessInstanceImpl.java:230) at org.drools.common.AbstractWorkingMemory.startProcess( AbstractWorkingMemory.java:1639) at org.drools.common.AbstractWorkingMemory.startProcess( AbstractWorkingMemory.java:1604) at org.drools.impl.StatefulKnowledgeSessionImpl.startProcess( StatefulKnowledgeSessionImpl.java:267) at br.com.pst.packages.ServicePackages.main( ServicePackages.java:99) ] Actually, the beginning problem was with my project, with a process and subprocess. The subprocess works fine, but the main process throws a java.lang.NoSuchMethodError always on any node I put after a specific RuleFlowGroup node. Everyting used to work before, but when I begin to enlarge it, nothing seems to work anymore. And, as I told, I can't always guess the exact problem as the thrown exceptions are very generic. Hope anyone could help me! Thanks a lot ANA FLÁVIA FONSECA DOS SANTOS Analista de Desenvolvimento de Software PST Eletrônica S/A Phone: +55 19 3787 6379 aflavia(a)pst.com.br www.pst.com.br www.positron.com.br