Hi all,

I'm currently developing a Web application using WebSphere 6.0, Struts 1.3.9 and Hibernate 3.2.5.

I was managing the DB connection pool with Hibernate, but now I'm trying to manage it with a WebSphere datasource (DS). I'm using CMT Transactions.

The DS is properly configured (I think) and I can access to DB using Hibernate, but there is a problem:

If I use:

sessionFactory.openSession();

and then I use the session, it works fine, but if I try to use the following code:

Session session = sessionFactory.getCurrentSession();

An HibernateException is thrown:

org.hibernate.HibernateException: Current transaction is not in progress
at org.hibernate.context.JTASessionContext.currentSession(JTASessionContext.java:67)
at org.hibernate.impl.SessionFactoryImpl.getCurrentSession(SessionFactoryImpl.java:544)
at picage.model.dao.AdminUtilizadoresHome.findByExample(AdminUtilizadoresHome.java)
at picage.actions.AuthenticationAction.execute(AuthenticationAction.java:72)
at org.apache.struts.chain.commands.servlet.ExecuteAction.execute(ExecuteAction.java:58)
at org.apache.struts.chain.commands.AbstractExecuteAction.execute(AbstractExecuteAction.java:67)
at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51)
at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190)
at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:304)
at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:190)
at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
(...)


The Hibernate.cfg.xml is the following:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory name="java:hibernate/PICAGESessionFactory">
<property name="hibernate.session_factory_name">PICAGESessionFactory</property>

<property name="hibernate.connection.datasource">jdbc/picageDs</property>
<property name="hibernate.dialect">picage.utils.PlatformOracleDialect</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.CMTTransactionFactory</property>
<property name="hibernate.transaction.manager_lookup_class">org.hibernate.transaction.WebSphereExtendedJTATransactionLookup</property>
<property name="jta.UserTransaction">java:comp/UserTransaction</property>
<property name="hibernate.connection.pool_size">10</property>

<property name="hibernate.show_sql">true</property>
<property name="hibernate.format_sql">false</property>

<property name="hibernate.bytecode.use_reflection_optimizer">false</property>
<property name="hibernate.cache.provider_class">org.hibernate.cache.NoCacheProvider</property>
<property name="hibernate.connection.autocommit">true</property>
<property name="hibernate.current_session_context_class">jta</property>
<property name="hibernate.jdbc.use_streams_for_binary">true</property>
<property name="hibernate.jdbc.use_get_generated_keys">true</property>
<property name="hibernate.connection.autoReconnect">true</property>
<property name="hibernate.connection.autoReconnectForPools">true</property>
<property name="hibernate.connection.is-connection-validation-required">true</property>

<!-- Mappings... -->


Does any one know why I can't use getCurrentSession()?

Thanks


Cheers

Because you are using a CMT transaction lookup but the call to currentSession is not within the scope of a transaction. Switching to a JTA transaction lookup might solve the problem (I know JTA transaction manager will start a transaction unless any transaction is present but I am not sure if this applies to call to currentSession). Alternatively you could get an instance of UserTransaction and start a transaction before calling currentSession. Spring will do the trick too.



Farzad-

Hi,

Thank you for your answer, but I had already tried all that and it didn't work. I'm not using Spring, so that is not an option.

I think that the problem is that when I try to get (by hand) userTransaction from JNDI using "java:comp/UserTransaction" it does not work.

Do you know if this must be configured in WebSphere or Hibernate or somewhere else?


Thanks again :)

Luis

I don't quite understand what you mean when you get a user transaction it doesn't work. Do you get an exception? In addition, Spring should do it for you. What is your spring configuration?


Farzad-

Hi,

I finally understood why I couldn't use getCurrentSession(). The problem is that there is no CMT in a web application. At least this was what I could find after several hours of google and hibernate research...

The solution, for me, was to use the following config in hibernate.cfg.xml:

<property name="hibernate.transaction.manager_lookup_class">org.hibernate.transaction.WebSphereExtendedJTATransactionLookup</property>
<property name="jta.UserTransaction">java:comp/UserTransaction</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<property name="hibernate.current_session_context_class">thread</property>

and then the getCurrentSession() worked just fine.


The only thing that I still can not understand with the previous config is:
why can I open a new session and in the next line of code, if I call getCurrentSession(), it throws an HibernateException?

Thanks.

Luis

Because open session just creates the objects. It doesn't really hook into anything before you actually need to use it. currentSession seeks for an open and bound-to-current-thread session.


Farzad-

Hi LMR, went exactly thru the same hell. There is some article on IBM Developworks

http://www.ibm.com/developerworks/websp ... lcott.html

which recommedns the CMTT Factory but obviosuly this is only working in an EJB module. The other option is to use bean managed transactions. These are the options:

#

for container-managed transactions:

<property name="hibernate.transaction.factory_class">
org.hibernate.transaction.CMTTransactionFactory
</property>
<property name="hibernate.transaction.manager_lookup_class">
org.hibernate.transaction.WebSphereExtendedJTATransactionLookup
</property>


#

for bean-managed transactions:

<property name="hibernate.transaction.factory_class">
org.hibernate.transaction.JTATransactionFactory
</property>
<property name="hibernate.transaction.manager_lookup_class">
org.hibernate.transaction.WebSphereExtendedJTATransactionLookup
</property>
<property name="jta.UserTransaction">
java:comp/UserTransaction
</property >

However, none of them works for me.
The only solution is to use

org.hibernate.transaction.JDBCTransactionFactory

as TRX factory.
Do you have any new insights, why this might be the case?

Is it a webapp or a standalone app?


Farzad-

Hi,

It's a Web-App only, no EJB modules.

It's a better idea to use JDBC transactions if database is the only transactional resource in your application.



Farzad-

sure, there is no need to use JDBC Tx management but I simply don't understand why it's not working... It is either a HB or a WAS issue.

WebSphere does not implement standard transaction management technology so there are certain feature that are not available when working with WebSphere. If you still need to use a JTA manager then you might want to use a CMTTransactionFactory and make sure transaction are started before interacting with hibernate. That will work.




Farzad-

I know WAS is a PITA when it comes to standards compliance... will stick with JDBC. thanks