[jboss-user] [jBPM] - NullPointerException when instantiating TaskService to start MinaTaskServer

gvallangca [https://community.jboss.org/people/gvallangca] created the discussion "NullPointerException when instantiating TaskService to start MinaTaskServer" To view the discussion, visit: https://community.jboss.org/message/750944#750944 -------------------------------------------------------------- Hi, I'm having a problem running my code to start my MinaTaskServer. I'm encountering a NullPointerException to the highlighted red line.     @PersistenceContext(unitName = "org.jbpm.persistence.jpa")           private EntityManager em;      public void startMinaServer() throws Exception {           System.out.println("********** Initializing MinaTask Server **********");                     System.out.println("em.getEntityManagerFactory(): " + em.getEntityManagerFactory());                     System.out.println("SystemEventListenerFactory.getSystemEventListener(): " + SystemEventListenerFactory.getSystemEventListener()); TaskService taskService = new TaskService(em.getEntityManagerFactory(), SystemEventListenerFactory.getSystemEventListener());                     TaskServiceSession taskSession = taskService.createSession();                     taskSession.addUser(new User("gvallangca"));                     minaServer = new MinaTaskServer(taskService);                     minaThread = new Thread(minaServer);                     minaThread.start();       } This is what is written in my *persistence.xml*: <persistence-unit name="org.jbpm.persistence.jpa" transaction-type="JTA">         <provider>org.hibernate.ejb.HibernatePersistence</provider>         <jta-data-source>java:jdbc/jbpm</jta-data-source>         <class>org.jbpm.task.Attachment</class>         <class>org.jbpm.task.Content</class>         <class>org.jbpm.task.BooleanExpression</class>         <class>org.jbpm.task.Comment</class>         <class>org.jbpm.task.Deadline</class>         <class>org.jbpm.task.Comment</class>         <class>org.jbpm.task.Deadline</class>         <class>org.jbpm.task.Delegation</class>         <class>org.jbpm.task.Escalation</class>         <class>org.jbpm.task.Group</class>         <class>org.jbpm.task.I18NText</class>         <class>org.jbpm.task.Notification</class>         <class>org.jbpm.task.EmailNotification</class>         <class>org.jbpm.task.EmailNotificationHeader</class>         <class>org.jbpm.task.PeopleAssignments</class>         <class>org.jbpm.task.Reassignment</class>         <class>org.jbpm.task.Status</class>         <class>org.jbpm.task.Task</class>         <class>org.jbpm.task.TaskData</class>         <class>org.jbpm.task.SubTasksStrategy</class>         <class>org.jbpm.task.OnParentAbortAllSubTasksEndStrategy</class>         <class>org.jbpm.task.OnAllSubTasksEndParentEndStrategy</class>         <class>org.jbpm.task.User</class>                   <class>org.drools.persistence.info.SessionInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceEventInfo</class>         <class>org.drools.persistence.info.WorkItemInfo</class>         <properties>              <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>         </properties>   </persistence-unit> Can anybody help me to determine what wrong or missing? Thank you so much. -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/750944#750944] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]