StaleObjectStateException ERROR - please help

Question

Hi,

Anyone can point me to the error please?

Note: this is a simplified test case extracted from my real app. Thus the weird usage of 3 entity managers and em1.getTransaction().begin(); em1.clear(); em1.close(); at the end of each section. In real app it happens in different times. HibernateUtil is basically copied from the tutorial.

        HibernateUtil.open();

        EntityManager em1 = HibernateUtil.reserveEntityManager();
        em1.getTransaction().begin();
        StringType st1 = new StringType();
        st1.setName("a");
        em1.persist(st1);
        em1.getTransaction().commit();
        em1.getTransaction().begin();
        em1.clear();
        em1.close();

        EntityManager em2 = HibernateUtil.reserveEntityManager();
        em2.getTransaction().begin();
        StringType st2 = new StringType();
        st2.setName("a");
        st2.setId(st1.getId());
        em2.merge(st2);
        em2.getTransaction().commit();
        em2.getTransaction().begin();
        em2.clear();
        em2.close();

        EntityManager em3 = HibernateUtil.reserveEntityManager();
        em3.getTransaction().begin();
        StringType st3 = new StringType();
        st3.setName("a");
        st3.setId(st1.getId());
        [b]em3.merge(st3);[/b]
        em3.getTransaction().commit();
        em3.getTransaction().begin();
        em3.clear();
        em3.close();



public static EntityManager reserveEntityManager()
    {
        return emf.createEntityManager();
    }

public static void open()
    {
        try
        {           
            emf = Persistence.createEntityManagerFactory("manager1");
        }
        catch (Throwable e)
        {
            throw new ExceptionInInitializerError(e);
        }
    }

javax.persistence.OptimisticLockException: org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): [WebOrganizer.classes.types.StringType#174] at org.hibernate.ejb.AbstractEntityManagerImpl.wrapStaleStateException(AbstractEntityManagerImpl.java:646) at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:600) at org.hibernate.ejb.AbstractEntityManagerImpl.merge(AbstractEntityManagerImpl.java:237) at WebOrganizer.web.servlets.TypeServlet.test2(TypeServlet.java:356) 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 org.testng.internal.MethodHelper.invokeMethod(MethodHelper.java:580) at org.testng.internal.Invoker.invokeMethod(Invoker.java:517) at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:669) at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:956) at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:126) at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:110) at org.testng.TestRunner.runWorkers(TestRunner.java:720) at org.testng.TestRunner.privateRun(TestRunner.java:590) at org.testng.TestRunner.run(TestRunner.java:484) at org.testng.SuiteRunner.runTest(SuiteRunner.java:332) at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:327) at org.testng.SuiteRunner.privateRun(SuiteRunner.java:299) at org.testng.SuiteRunner.run(SuiteRunner.java:204) at org.testng.TestNG.createAndRunSuiteRunners(TestNG.java:864) at org.testng.TestNG.runSuitesLocally(TestNG.java:830) at org.testng.TestNG.run(TestNG.java:748) at org.testng.remote.RemoteTestNG.run(RemoteTestNG.java:73) at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:124) 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 com.intellij.rt.execution.application.AppMain.main(AppMain.java:90)

Caused by: org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): [WebOrganizer.classes.types.StringType#174] at org.hibernate.event.def.DefaultMergeEventListener.entityIsDetached(DefaultMergeEventListener.java:261) at org.hibernate.event.def.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:120) at org.hibernate.event.def.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:53) at org.hibernate.impl.SessionImpl.fireMerge(SessionImpl.java:677) at org.hibernate.impl.SessionImpl.merge(SessionImpl.java:661) at org.hibernate.impl.SessionImpl.merge(SessionImpl.java:665) at org.hibernate.ejb.AbstractEntityManagerImpl.merge(AbstractEntityManagerImpl.java:228) ... 28 more

Answer 1

I'd give something like this a try:

EntityTransaction tx1 = em1.getTransaction();
// make your modifications
em1.merge(st1);
tx1.commit();

Not sure why you have are beginning a transaction right before you clean up the EntityManager. I don't work with JPA transactions programmatically so this is just an educated guess. Also, why are you creating a new EntityManager every time if it's returning the same instance?

Answer 2

This example is extracted from a larger code. The 3 parts happen in different times, but always on the same object.