Amin Hosseiny Marani [https://community.jboss.org/people/aminhosseiny] created the discussion "problem in making a simple human task" To view the discussion, visit: https://community.jboss.org/message/714653#714653 -------------------------------------------------------------- i try to do something that http://www.mastertheboss.com/jbpm/346-human-tasks-in-jbpm-5.html this url mentioned it...but unfortunatley these exception come to me! my code public class ProcessTest {             public static final void main(String[] args) {                     try {                               startUp();                               KnowledgeBase kbase = readKnowledgeBase();       line 31:                            StatefulKnowledgeSession ksession = JBPMHelper.newStatefulKnowledgeSession(kbase);                                   ksession.startProcess("human_process");                               System.out.println("Process started ...");                           } catch (Throwable t) {                               t.printStackTrace();                     }           }             private static KnowledgeBase readKnowledgeBase() throws Exception {                     KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();                     kbuilder.add(ResourceFactory.newClassPathResource("sample2.bpmn"), ResourceType.BPMN2);                     return kbuilder.newKnowledgeBase();           }     private static void startUp()           {                     JBPMHelper.startH2Server();                     JBPMHelper.setupDataSource();             }   the exceptions : javax.persistence.PersistenceException: [PersistenceUnit: org.jbpm.persistence.jpa] Unable to build EntityManagerFactory           at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:677)           at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:126)           at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:52)           at org.jbpm.test.JBPMHelper.loadStatefulKnowledgeSession(JBPMHelper.java:138)           at org.jbpm.test.JBPMHelper.newStatefulKnowledgeSession(JBPMHelper.java:127)           at com.sample.ProcessTest.main(ProcessTest.java:31) Caused by: org.hibernate.HibernateException: Could not obtain BTM transaction manager instance           at org.hibernate.transaction.BTMTransactionManagerLookup.getTransactionManager(BTMTransactionManagerLookup.java:50)           at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:367)           at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1341)           at org.hibernate.cfg.AnnotationConfiguration.buildSessionFactory(AnnotationConfiguration.java:867)           at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:669)           ... 5 more Caused by: java.lang.reflect.InvocationTargetException           at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)           at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)           at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)           at java.lang.reflect.Method.invoke(Method.java:597)           at org.hibernate.transaction.BTMTransactionManagerLookup.getTransactionManager(BTMTransactionManagerLookup.java:47)           ... 9 more Caused by: bitronix.tm.utils.InitializationException: cannot open disk journal           at bitronix.tm.BitronixTransactionManager.<init>(BitronixTransactionManager.java:75)           at bitronix.tm.TransactionManagerServices.getTransactionManager(TransactionManagerServices.java:62)           ... 14 more Caused by: java.io.IOException: transaction log file btm2.tlog is locked. Is another instance already running?           at bitronix.tm.journal.TransactionLogAppender.<init>(TransactionLogAppender.java:72)           at bitronix.tm.journal.DiskJournal.open(DiskJournal.java:152)           at bitronix.tm.BitronixTransactionManager.<init>(BitronixTransactionManager.java:62)           ... 15 more -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/714653#714653] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]