Bug : Getting NullPointerException when getting the ProcessInstance p = ksession.getProcessInstance(id)

[uvijayreddy657]

Below is the stacktrace:

java.lang.NullPointerException

at org.jbpm.process.instance.impl.ProcessInstanceImpl.setProcess(ProcessInstanceImpl.java:61)

at org.jbpm.marshalling.impl.AbstractProcessInstanceMarshaller.readProcessInstance(AbstractProcessInstanceMarshaller.java:380)

at org.jbpm.persistence.processinstance.ProcessInstanceInfo.getProcessInstance(ProcessInstanceInfo.java:133)

at org.jbpm.persistence.processinstance.JPAProcessInstanceManager.getProcessInstance(JPAProcessInstanceManager.java:64)

at org.jbpm.process.instance.ProcessRuntimeImpl.getProcessInstance(ProcessRuntimeImpl.java:190)

at org.drools.common.AbstractWorkingMemory.getProcessInstance(AbstractWorkingMemory.java:1113)

at org.drools.impl.StatefulKnowledgeSessionImpl.getProcessInstance(StatefulKnowledgeSessionImpl.java:283)

at org.drools.command.runtime.process.GetProcessInstanceCommand.execute(GetProcessInstanceCommand.java:48)

at org.drools.command.runtime.process.GetProcessInstanceCommand.execute(GetProcessInstanceCommand.java:25)

at org.drools.persistence.SingleSessionCommandService.execute(SingleSessionCommandService.java:292)

at org.drools.command.impl.CommandBasedStatefulKnowledgeSession.getProcessInstance(CommandBasedStatefulKnowledgeSession.java:124)

at com.emirates.sds.workflow.bpmn.engine.CWFEngine.getProcessInstance(CWFEngine.java:225)

at com.emirates.sds.workflow.mbean.CWorkflowDesignerMBean.getAssignedTasks(CWorkflowDesignerMBean.java:739)

at com.emirates.sds.workflow.mbean.CWorkflowDesignerMBean.getTasks(CWorkflowDesignerMBean.java:1217)

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 javax.el.BeanELResolver.getValue(BeanELResolver.java:62)

at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)

at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:71)

at org.apache.el.parser.AstValue.getValue(AstValue.java:118)

at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)

at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:71)

at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:190)

at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:178)

at javax.faces.component.UIData.getValue(UIData.java:554)

at org.ajax4jsf.component.UIDataAdaptorBase.getValue(UIDataAdaptorBase.java:1647)

at org.ajax4jsf.component.SequenceDataAdaptor.getDataModel(SequenceDataAdaptor.java:65)

at org.richfaces.component.UIExtendedDataTable.resetDataModel(UIExtendedDataTable.java:390)

at org.ajax4jsf.component.UIDataAdaptorBase.beforeRenderResponse(UIDataAdaptorBase.java:1656)

at org.richfaces.component.UIExtendedDataTable.beforeRenderResponse(UIExtendedDataTable.java:417)

at org.ajax4jsf.component.RenderPhaseUIDataAdaptorVisitor.beforeComponent(RenderPhaseUIDataAdaptorVisitor.java:44)

at org.richfaces.event.RenderPhaseComponentListener.processComponents(RenderPhaseComponentListener.java:47)

at org.richfaces.event.RenderPhaseComponentListener.processComponents(RenderPhaseComponentListener.java:55)

at org.richfaces.event.RenderPhaseComponentListener.processComponents(RenderPhaseComponentListener.java:55)

at org.richfaces.event.RenderPhaseComponentListener.processComponents(RenderPhaseComponentListener.java:55)

at org.richfaces.event.RenderPhaseComponentListener.beforePhase(RenderPhaseComponentListener.java:71)

at org.ajax4jsf.component.AjaxViewRoot.processPhaseListeners(AjaxViewRoot.java:188)

at org.ajax4jsf.component.AjaxViewRoot.encodeBegin(AjaxViewRoot.java:510)

at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1641)

at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:592)

at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:100)

at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:176)

at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:117)

at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:97)

at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:135)

at javax.faces.webapp.FacesServlet.service(FacesServlet.java:309)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:206)

at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290)

at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:388)

at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:515)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

at org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:349)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)

at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)

at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)

at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)

at java.lang.Thread.run(Thread.java:619)

[tsurdilovic]

Check your process bpmn, your process should have an the id attribute set.

Hope this helps.

[uvijayreddy657]

Actually this issue is araising when I restart my development server.

Case is: I am trying get the assigned task list of User. From Task object when I am trying to get ProcessInstanceId and from this proessInstanceId I am trying to get RuleFlowProcess object. when getting RuleFlowProcess object I am getting the NullPointerException internally in the framework.

ProcessInstance processInstance =

ProcessInstance processInstance = ksession.getProcessInstance(task.getProcessInstanceId());

RuleFlowProcess process = (RuleFlowProcess) kbase.getProcess(processInstance.getProcessId());  // in this line I am getting the exception

This may be  happening because of new kbase initialization on every server startup. How to avoid this? how to get the exisiting KnowledgeBase?