Query after exception in transaction?

trancer_hibernate · **Joined:** Wed Sep 20, 2006 6:33 am **Posts:** 5

Hibernate version: 3.1

Mapping documents:

Code:

<class name="ru.myapp.model.Tag" table="tag">
  <id name="id" column="id" type="long">
    <generator class="identity"/>
  </id>
  
  <property name="name" column="name"/>
</class>

Code between sessionFactory.openSession() and session.close():

Code:

Session s = sf.openSession();
Transaction tx = null;
try
{
   tx = s.beginTransaction();

   Tag t = new Tag();
   t.setName("a");
   s.save(t);

   tx.commit();
}
catch (HibernateException e)
{
   if (tx != null)
   {
      Tag t1 = (Tag) s.createQuery("from Tag where name=:name").setString("name", "a").list().get(0);
      System.out.println("loaded tag id: " + t1.getId());
      System.out.println("loaded tag name: " + t1.getName());

      tx.rollback();
   }
}
finally
{
   s.close();
}

Full stack trace of any exception that occurs:

Code:

org.hibernate.AssertionFailure: null id in ru.myapp.model.Tag entry (don't flush the Session after an exception occurs)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:48)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:150)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:106)
   at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:195)
   at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:76)
   at org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:35)
   at org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:951)
   at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:109)
   at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:88)
   at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1540)
   at test.HSessionFactoryTest.main(HSessionFactoryTest.java:78)
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
Exception in thread "main" org.hibernate.AssertionFailure: null id in ru.myapp.model.Tag entry (don't flush the Session after an exception occurs)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:48)
   at java.lang.reflect.Method.invoke(Method.java:585)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:150)
   at com.intellij.rt.execution.application.AppMain.main(AppMain.java:90)
   at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:106)
   at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:195)
   at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:76)
   at org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:35)
   at org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:951)
   at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:109)
   at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:88)
   at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1540)
   at test.HSessionFactoryTest.main(HSessionFactoryTest.java:78)
   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:585)
   at com.intellij.rt.execution.application.AppMain.main(AppMain.java:90)

Name and version of the database you are using:
mysql version 5.0.24, tabel type is MyISAM

Hello.

I have the following situation. The table Tag holds tags as id and name. Name of a tag is UNIQUE. I want, when a new tag is added and it is already exists, to load an existing tag, but I get the following exception as shown above. How to make a query after an exception occurs during a transaction. In the example above the exception occurs due to the UNIQUE constraint on the name field.

Thank you.

christian · **Posted:** Thu May 10, 2007 5:50 am

You can not ever use a Session again after it has thrown an exception. Read the documentation.

trancer_hibernate · **Joined:** Wed Sep 20, 2006 6:33 am **Posts:** 5

But what if I get this exception in OpenSessionInViewFilter?

The whole picture is the following:
A user adds tags to entities. During a request my webapp creates a tag and if it exists it adds an existing tag to an entity? But when during creation an exception occurs then I cannot load an existing tag and add it to an entity?

Could you, please, explain?