Hi,
here's the configuration I'm working with:
Hibernate version: 2
JBoss version: 4.0

Here's the problem: I get the hibernate session from org.jboss.hibernate.session.HibernateContext inside a Stateless Session Bean. see: http://www.jboss.org/wiki/Wiki.jsp?page=JBossHibernate. The session bean tries to save an object using hibernate. Upon calling session.save(persistentObject); I get the following exception:

Caused by: java.sql.SQLException: You cannot set autocommit during a managed transaction!
at org.jboss.resource.adapter.jdbc.BaseWrapperManagedConnection.setJdbcAutoCommit(BaseWrapperManagedConnection.java:442)
at org.jboss.resource.adapter.jdbc.WrappedConnection.setAutoCommit(WrappedConnection.java:432)
at net.sf.hibernate.id.TableGenerator.generate(TableGenerator.java:85)
at net.sf.hibernate.id.TableHiLoGenerator.generate(TableHiLoGenerator.java:59)
at net.sf.hibernate.impl.SessionImpl.saveWithGeneratedIdentifier(SessionImpl.java:776)


Upon reading the source code, turns out that TableGenerator.generate() calls conn.setAutoCommit(false); to ensure that the generated id is unique across the transaction context. However, this a container managed transaction and so the jboss managedConnection wrapper (BaseWrapperManageConnection) throws an exception when setAutoCommit(false) is called.
How can I resolve this problem? Any help would be much appreciated!

As the documentation clearly states, you can not use hilo in a managed environment.

There is a way but you have to implement you own id generator. Have a look at
http://cvs.sourceforge.net/viewcvs.py/jboss/jboss-ejb3/src/main/org/jboss/ejb3/entity/JTATableIdGenerator.java?rev=1.1&view=auto

Here is something strange. I am experiencing the exact same problem. However, I am not using hilo for any of my object.

Hibernate Version: 2.1.7
Jboss Version: 4.0.1

Is there any reason why hibernate would use hilo when I'm clearly using a sequence? Here is my mapping file for the object I'm attempting to save. (Sorry for the Xdoclet garbage)

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping
>
<class
name="com.avaloninc.account.data.Group"
table="groups"
lazy="true"
dynamic-update="false"
dynamic-insert="false"
select-before-update="false"
optimistic-lock="version"
>
<cache usage="transactional" />

<id
name="id"
column="group_id"
type="java.lang.Long"
access="property"
>
<generator class="native">
<param name="sequence">group_seq</param>
</generator>
</id>

<property
name="created"
type="java.util.Date"
update="false"
insert="true"
access="net.sf.hibernate.property.DirectPropertyAccessor"
column="created"
not-null="true"
/>

<property
name="name"
type="java.lang.String"
update="true"
insert="true"
access="property"
column="name"
not-null="true"
/>

<property
name="defaultGroup"
type="java.lang.Boolean"
update="true"
insert="true"
access="property"
column="default_group"
not-null="true"
/>

<property
name="disabled"
type="boolean"
update="true"
insert="true"
access="property"
column="disabled"
not-null="true"
/>

</class>

</hibernate-mapping>

Nevermind....found the problem. It appeared to be because of a faulty custom dialect I was using. :)

Mike

BTW, we've implemented the JTA-enabled hilo generator in H3beta2