Hi, i deeply appreciate anyone who can provide any solution to this problem which i have been
trying to solve for the past 5 days but to no avail. I am facing this show-stopper in my project now. Any experts here can help me?

I am using Sun One App Server 7, Oracle 9i and Hibernate 3 for my project.

Below is my hibernate.cfg.xml

<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD //EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="connection.datasource">jdbc/myDataSource</property>
<property name="transaction.factory.class">org.hibernate.transaction.JTATransactionFactory</property>
<property name="hibernate.transaction.manager_lookup_class">framework.persistence.SunONETransactionManager</property>
<property name="dialect">org.hibernate.dialect.OracleDialect</property>
<property name="hibernate.show_sql">true</property>
<mapping resource="RoleFunctionAssignment.hbm.xml"/>
</session-factory>
</hibernate-configuration>


From above you can see that i am trying to use the SunOneTransactionManager...the code shown below was found in this forum too.

import javax.transaction.TransactionManager;
import java.util.Properties;
import com.sun.enterprise.Switch;

public class SunONETransactionManager implements TransactionManagerLookup {

public TransactionManager getTransactionManager(Properties properties) {
return Switch.getSwitch().getTransactionManager();
}

public String getUserTransactionName() {
return "UserTransaction";
}
}

I try to register the transaction as shown below in a class called HibernateUtil.java

public static Session currentSession() throws HibernateException {
Session s = (Session) session.get();
if (s == null) {
s = sessionFactory.openSession();
session.set(s);
}
try {

TransactionManager trxMgr = Switch.getSwitch().getTransactionManager();
trxMgr.begin();
javax.transaction.Transaction trx = trxMgr.getTransaction();

if (trx != null) {
trx.registerSynchronization(new HibernateSynchronisation());
}
}
catch (Exception e) {
e.printStackTrace();
} return s;
}


public class HibernateSynchronisation
implements Synchronization {

public void beforeCompletion() {

}

public void afterCompletion(int arg0) {
HibernateUtil.closeSession();
}
}
What HibernateUtil.closeSession tries to do is shown below:

session.set(null);
if (s != null && s.isOpen()) {
s.close();
}
The problem arise when whenever I try to perform more than 1 tasks in 1 action class like for example shown below,
I will get the following error.

WARNING: CORE3283: stderr: javax.transaction.NotSupportedException: Nested trans
action not supported

User user = (User) udao.create(user);
User user1 = (User)udao.findByPrimaryKey(user.getId().longValue());

If i only perform 1 task like create in 1 action class, the exception will not be thrown.

What should i do? I have tried to commit the transaction manually in the Hibernate.closeSession method.. but
it throws other exceptions.

Can any experts please help me on this issue?