Jing Zhang [http://community.jboss.org/people/zhangjing2000] created the discussion "NPE caused by Bitronix transaction glitch or drools transaction issue?" To view the discussion, visit: http://community.jboss.org/message/619281#619281 -------------------------------------------------------------- I wrote a simple java code to test jBPM5.1's JPAKnowledgeService.  I used Bitronix as transaction manager and H2 as database. The test java code could start a process, completed a work item and then ended the process successfully, but when I added a method call WorkflowProcessInstance.getNodeInstances().iterator().next().getNodeName() after starting the process instance, a NPE was caught. I found it is due to ProcessInstanceImpl.kruntime is null. After traced the startProcess's execution path, found ProcessInstanceImpl.kruntime has been reset to null after transaction committed in method org.drools.persistence.SingleSessionCommandService.execute(Command<T> command). Not sure if this is a Bitronix transaction issue or a jBPM5.1 transaction issue. -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/619281#619281] Start a new discussion in jBPM at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]