[jbpm-issues] [JBoss JIRA] Commented: (JBPM-2607) org.hibernate.NonUniqueResultException when task completion results in the assignment of a subsequent task to the same user

org.hibernate.NonUniqueResultException when task completion results in the assignment of a subsequent task to the same user --------------------------------------------------------------------------------------------------------------------------- Key: JBPM-2607 URL: https://jira.jboss.org/jira/browse/JBPM-2607 Project: jBPM Issue Type: Bug Security Level: Public(Everyone can see) Components: Runtime Engine Affects Versions: jBPM 4.1 Environment: OS: Mac OS X 10.6 java version "1.6.0_15" Java(TM) SE Runtime Environment (build 1.6.0_15-b03-219) Java HotSpot(TM) 64-Bit Server VM (build 14.1-b02-90, mixed mode) DB: MySQL 5 and HSQL Reporter: Nils Preusker Fix For: jBPM 4.x Attachments: MultipleTasksTest.java, process.jpdl.xml The exception occurs when two subsequent tasks are both assigned to the same person and the second task contains a notification node. When the first task is completed, the MailListener will use the findTaskByExecution method of DbSessionImpl.java, which in turn queries the database for tasks by execution. I'm not sure if accidentally two instances of the same task are inserted into the database or if the previous task is not yet removed, but the query apparently returns two results, so the "uniqueResult()" call throws a NonUniqueResultException. (See attached process and unit test for details, this can also be found in the forum at http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4262559#...)