jess singh [https://community.jboss.org/people/singhjess] created the discussion "Nullpointer exception when retrieveing tasks for a user" To view the discussion, visit: https://community.jboss.org/message/747629#747629 -------------------------------------------------------------- I am using JBPM 5.3 with Jboss 7.1 and Seam managed persistence context here is my persistence.xml <persistence xmlns=" http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence"     xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance http://www.w3.org/2001/XMLSchema-instance"     xsi:schemaLocation=" http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"     version="2.0">     <persistence-unit name="main" transaction-type="JTA">         <description>Forge Persistence Unit</description>         <provider>org.hibernate.ejb.HibernatePersistence</provider>         <jta-data-source>java:jboss/datasources/oracleDS</jta-data-source>         <mapping-file>META-INF/JBPMOrm-JPA2.xml</mapping-file>         <mapping-file>META-INF/Taskorm.xml</mapping-file>         <class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>         <class>org.drools.persistence.info.SessionInfo</class>         <class>org.drools.persistence.info.WorkItemInfo</class>         <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>         <exclude-unlisted-classes>false</exclude-unlisted-classes>         <!-- <class>org.jbpm.process.audit.ProcessInstanceLog</class> <class>org.jbpm.process.audit.NodeInstanceLog</class>             <class>org.jbpm.process.audit.VariableInstanceLog</class> -->         <properties>             <property name="hibernate.hbm2ddl.auto" value="update" />             <property name="hibernate.transaction.flush_before_completion"                 value="true" />             <property name="hibernate.show_sql" value="true" />             <property name="hibernate.format_sql" value="true" />             <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect" />     <!--                      <property name="hibernate.transaction.manager_lookup_class"                 value="org.hibernate.transaction.JBossTransactionManagerLookup" />     -->         </properties>     </persistence-unit> </persistence> here is the code  - @Resource( mappedName = "java:/TransactionManager" )     private TransactionManager tm;     @Inject     private UserTransaction ut;     public void startProcess() {         try {             // getUserTransaction().begin();             new TaskManagerServer().startServer();             KnowledgeBase kbase = readKnowledgeBase();             TransactionManager manager = (TransactionManager) new InitialContext().lookup( "java:jboss/TransactionManager" );             //manager.begin();             // create the entity manager factory and register it in the environment             EntityManagerFactory emf = EMFactory.getEntityManagerFactory(); // Persistence.createEntityManagerFactory( "main" );             Environment env = KnowledgeBaseFactory.newEnvironment();             env.set( EnvironmentName.ENTITY_MANAGER_FACTORY, emf );              env.set( EnvironmentName.TRANSACTION, ut );             env.set( EnvironmentName.GLOBALS, new MapGlobalResolver() );             env.set( EnvironmentName.APP_SCOPED_ENTITY_MANAGER, entityManager );             env.set( EnvironmentName.TRANSACTION_MANAGER, manager );             Map<String,Object> params = new HashMap<String,Object>();             params.put( "name", "Arthur" );             params.put( "money", 800 );             // create a new knowledge session that uses JPA to store the runtime state             StatefulKnowledgeSession ksession = JPAKnowledgeService.newStatefulKnowledgeSession( kbase, null, env );             AsyncMinaHTWorkItemHandler handler = new AsyncMinaHTWorkItemHandler( ksession );             // CommandBasedWSHumanTaskHandler handler = new CommandBasedWSHumanTaskHandler( ksession );             ksession.getWorkItemManager().registerWorkItemHandler( "Human Task", handler );             String name = "ksclient-" + UUID.randomUUID();             // invoke methods on your method here             ksession.startProcess( "process_1", params );             TaskClient client = new TaskClient( new MinaTaskClientConnector( name, new MinaTaskClientHandler(                             SystemEventListenerFactory.getSystemEventListener() ) ) );             client.connect( "127.0.0.1", 9123 );             BlockingTaskSummaryResponseHandler taskSummaryResponseHandler = new BlockingTaskSummaryResponseHandler();             client.getTasksAssignedAsPotentialOwner( "john", "en-US", taskSummaryResponseHandler );   // this line throws but continues             List<TaskSummary> tasks = taskSummaryResponseHandler.getResults();   //  number of tasks is always zero             for ( TaskSummary taskSummary : tasks ) {                 System.out.println( taskSummary.getName() );             }             //manager.commit();             // getUserTransaction().commit();             // ksession.dispose();         } catch ( Throwable t ) {             t.printStackTrace();         }     } 405 ERROR [org.jbpm.task.service.TaskServerHandler] (NioProcessor-1) Could not start transaction.: java.lang.RuntimeException: Could not start transaction.     at org.jbpm.task.service.TaskServiceSession.doOperationInTransaction(TaskServiceSession.java:994) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.TaskServiceSession.addTask(TaskServiceSession.java:186) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.TaskServerHandler.messageReceived(TaskServerHandler.java:144) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.mina.MinaTaskServerHandler.messageReceived(MinaTaskServerHandler.java:41) [jbpm-human-task-mina-5.3.0.Final.jar:5.3.0.Final]     at org.apache.mina.core.filterchain.DefaultIoFilterChain$TailFilter.messageReceived(DefaultIoFilterChain.java:713) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilterChain.java:46) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceived(DefaultIoFilterChain.java:793) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.filter.codec.ProtocolCodecFilter$ProtocolDecoderOutputImpl.flush(ProtocolCodecFilter.java:375) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.filter.codec.ProtocolCodecFilter.messageReceived(ProtocolCodecFilter.java:229) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilterChain.java:46) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceived(DefaultIoFilterChain.java:793) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.filter.logging.LoggingFilter.messageReceived(LoggingFilter.java:176) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.access$1200(DefaultIoFilterChain.java:46) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain$EntryImpl$1.messageReceived(DefaultIoFilterChain.java:793) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.IoFilterAdapter.messageReceived(IoFilterAdapter.java:119) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.callNextMessageReceived(DefaultIoFilterChain.java:434) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.filterchain.DefaultIoFilterChain.fireMessageReceived(DefaultIoFilterChain.java:426) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.polling.AbstractPollingIoProcessor.read(AbstractPollingIoProcessor.java:638) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.polling.AbstractPollingIoProcessor.process(AbstractPollingIoProcessor.java:598) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.polling.AbstractPollingIoProcessor.process(AbstractPollingIoProcessor.java:587) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.polling.AbstractPollingIoProcessor.access$400(AbstractPollingIoProcessor.java:61) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run(AbstractPollingIoProcessor.java:969) [mina-core-2.0.0-RC1.jar:]     at org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:64) [mina-core-2.0.0-RC1.jar:]     at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [rt.jar:1.6.0_31]     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [rt.jar:1.6.0_31]     at java.lang.Thread.run(Thread.java:662) [rt.jar:1.6.0_31] Caused by: java.lang.NullPointerException     at org.drools.persistence.jta.JtaTransactionManager.getStatus(JtaTransactionManager.java:205) [drools-persistence-jpa-5.4.0.Final.jar:5.4.0.Final]     at org.jbpm.task.service.persistence.TaskJTATransactionManager.getStatus(TaskJTATransactionManager.java:63) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.persistence.TaskJTATransactionManager.begin(TaskJTATransactionManager.java:36) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.persistence.TaskPersistenceManager.beginTransaction(TaskPersistenceManager.java:79) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     at org.jbpm.task.service.TaskServiceSession.doOperationInTransaction(TaskServiceSession.java:976) [jbpm-human-task-core-5.3.0.Final.jar:5.3.0.Final]     ... 28 more -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/747629#747629] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]