Lazy Initaslization Error

[saurabh.khattar]

I have made a small BPM web application. In one of the methods in servlet I am getting the instances for a particular user:

private void getProcessDetails(HttpServletRequest request, HttpServletResponse response) {

 HttpSession session = request.getSession();

 List jbpmTaskInstances = new ArrayList();

 JbpmConfiguration jbpmConfiguration = JbpmEncompassConfiguration.instance().getJbpmConfiguration();
 JbpmContext jbpmContext = jbpmConfiguration.createJbpmContext();


 Session jbpmContextSession = jbpmContext.getSession();


 String actorPmId = new String("PM");
 String actorCordId = new String("Coordinator");

 List actorsList = new ArrayList();
 actorsList.add(actorPmId);
 List pooledPmTaskInstances = jbpmContext.getTaskMgmtSession().findTaskInstances(actorsList);
 List jbpmPmTaskInstanceList = jbpmContextSession.createQuery("from org.jbpm.taskmgmt.exe.TaskInstance ti where ti.start is null and ti.end is null and actorId = '"+actorPmId+"'").list();
 //add pooledTaskInstances to taskList
 jbpmPmTaskInstanceList.addAll(pooledPmTaskInstances);
 jbpmTaskInstances.addAll(jbpmPmTaskInstanceList);

 actorsList = new ArrayList();
 actorsList.add(actorCordId);
 List pooledCordTaskInstances = jbpmContext.getTaskMgmtSession().findTaskInstances(actorsList);
 List jbpmCordTaskInstanceList = jbpmContextSession.createQuery("from org.jbpm.taskmgmt.exe.TaskInstance ti where ti.start is null and ti.end is null and actorId = '"+actorCordId+"'").list();
 //add pooledTaskInstances to taskList
 jbpmCordTaskInstanceList.addAll(pooledCordTaskInstances);
 jbpmTaskInstances.addAll(jbpmCordTaskInstanceList);

 Iterator iAll = jbpmTaskInstances.iterator();
 Iterator iPm = jbpmPmTaskInstanceList.iterator();
 Iterator iCord = jbpmCordTaskInstanceList.iterator();

 List jbpmProcessInstances = new ArrayList();

 while(iAll.hasNext()){
 TaskInstance ti = (TaskInstance) iAll.next();
 ProcessInstance processInstance = ti.getProcessInstance();
 jbpmProcessInstances.add(processInstance);
 }



 session.setAttribute("pmTaskList", jbpmPmTaskInstanceList);
 session.setAttribute("cordTaskList", jbpmCordTaskInstanceList);
 session.setAttribute("allTaskList", jbpmProcessInstances);



 //jbpmContextSession.close();
 jbpmContext.close();

 }

I set arraylist of process instances in the session. But when I try to access process instances in jsp it gives the following error:

10:13:39,214 ERROR [LazyInitializationException] could not initialize proxy - the owning Session was closed
org.hibernate.LazyInitializationException: could not initialize proxy - the owning Session was closed
 at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:60)
 at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:111)
 at org.hibernate.proxy.pojo.cglib.CGLIBLazyInitializer.invoke(CGLIBLazyInitializer.java:172)
 at org.jbpm.graph.exe.ProcessInstance$$EnhancerByCGLIB$$614637f6.getContextInstance(<generated>)
 at org.apache.jsp.jsp.index_jsp._jspService(index_jsp.java:121)
 at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
 at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
 at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
 at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:175)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:74)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
 at org.jboss.web.tomcat.tc5.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:156)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
 at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
 at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
 at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
 at java.lang.Thread.run(Thread.java:595)

Please some one help me....

[kukeltje]

you put handles to processinstances in your list. Those are references, not the complete objecttrees (lazy loaded). If you act on one of the instances after the context is closed you get this. This is in fact a generic hibernate issue, not a jBPM issue.

[frantisek.kocun]

Hi, I had the same problem.
Look here: http://www.jboss.com/index.html?module=bb&op=viewtopic&t=140319
Either you can tag every reference in Hibernate mapping file for your business object as lazy="false", or register objects after getting them form contextInstance in hHibernate session. I don't like it, there must be better way. But I have observation, that business object will be registered later, because changes are stored to db. So I think there must be something in configuration of JBPM where to set that process variables should be registered in session all the time. I can't find where it is.

Please help

Fero