I have multiple oracle connection so i have to fire the transactions on all the datasources at once and if one fails, it gets rolled back on all or committed on all of them together.
How to achieve this with XADatasource ?
An XADataSource API provides two-phase commit to achieve this in a distributed environment. You need to make your DataSource Wrapper class using this API and the rest would be taken care by the API itself.
XA is best used with and app server like JBoss or WebSphere etc. But you can configure it in non-managed environments too.
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My project connects to a database using hibernate, getting connections from a connection pool on JBoss. I want to replace some of the reads/writes to tables with publish/consume from queues. I built a working example that uses OracleAQ, however, I am connecting to the DB using:
AQjmsFactory.getQueueConnectionFactory followed by createQueueConnection,
then using createQueueSession to get a (JMS) QueueSession on which I can call createProducer and createConsumer.
So I know how to do what I want using a jms.QueueSession. But using hibernate, I get a hibernate.session, which doesn't have those methods.
I don't want to open a new connection every time I perform an action on a queue - which is what I am doing now in my working example. Is there a way to perform queue operations from a hibernate.session? Only with SQL queries?
I think you're confusing a JMS (message queue) session with a Hibernate (database) session. The Hibernate framework doesn't have any overlap with JMS, so it can't be used to do both things.
You'll need 2 different sessions for this to work:
A Hibernate Session (org.hibernate.Session) for DB work
A JMS Session (javax.jms.Session) to to JMS/queue work
Depending on your use case, you may also want an XA transaction manager to do a proper two-phase commit across both sessions and maintain transactional integrity.
I was also looking for some "sane" way how to use JMS connection to manipulate database data. There is not any. Dean is right, you have to use two different connections to the same data and have distributed XA transaction between them.
This solution opens a world of various problems never seen before. In real life distributed transactions can really be non-trivial. Surprisingly in some situations Oracle can detect that two connections are pointing into the same database and then two-phase commit can be bypassed - even when using XA.
I have a situation to integrate two independent systems. One is using J2EE,EJBs and other is Spring based. Now the problem is both the systems can call methods of each other and i want to manage transactions as well. I am not sure how to coordinate both applications transaction managers as both are using different one (Spring and EJB).
Any one has an idea how to do this ?
First of all, both applications should use Extended transactions (XA transactions) on DataSource level (and for other resources such as Message Queues, JCA adapters or whatever resources you use in application).
Method calls should be done through Remote EJB call or web services that use WS-AtomicTransaction to handle transaction boundaries. If you do not want to change your architecture to add Remote EJBs, your best bet is to use web services with WS-AT that use XA transactions under the hood.
I am looking at using HornetQ as the Messaging Provider. I'd like to know what connection factory is suitable for what behavior/solution?
The connectionfactory is the base one. Specifically, javax.jms.ConnectionFactory is the java interface for JMS connection factories.
As it says in the documentation, HornetQ User Guide, Performance Tuning, you could use the pre configured ThroughputConnectionFactory for a tuned in CF for heavy load of small messages.
The XA ones are just prepared for global transactions through JTA when running inside JBoss AS. So you should go for these if you use multi resource transactions (such as Queue <-> DB transactions).
I have two level access to database: the first with Hibernate, the second with JDBC. The JDBC level work with nontransactional tables (I use MyISAM for speed). I want make both levels works within transaction. I read about JTA which can manage distributed transactions. But there is lack information in the internet about how to implement and use custom resource.
Does any one have experience with using custom XAResources?
I want make both levels works within transaction.
Then you'll have to change your storage engine for InnoDB, MyISAM tables do not support transactions (technically, you won't get an error but a rollback won't rollback anything).
Does any one have experience with using custom XAResources?
I'm not sure to understand what you're talking about. The only XA resource I see here is your database and you don't need to implement anything custom. What you need to do is to use XA connections very likely obtained from two XA DataSources (which are supported by MySQL Connector/J 5.0.0+), use the JTA API and let the Transaction Manager do its job .
But to be honest, you should really clarify your requirements. There might be other (and easier) options than using XA. And if all the above sounds like Chinese, then I have the feeling that don't use XA would be a good advice here.
Connection are obtained via a DataSource that can be configured to support distributed transaction or not. To use multiple connections in a distributed transaction, you must configure the multiple DataSource to support XA and return XA connections.
That said, you need several physical connections only if you connects to different database, which doesn't seem to be your case (that's not clear in the question).
A DataSource can be smart enough to make sure that the same physical connection is used as long as you are in the same thread; each time you ask for a connection, it actually returns a "handle" to the same physical connection, and the physical connection returns to the pool when all handles have been closed. (But that depends on the DataSource implementation).
Hibernate per se is not an XA resource: it uses underlying a connection obtained via a DataSource. But it hooks itself in the transaction manager via JTA, in particular to flush all pending changes before the distributed transaction commits.
You can most of the time obtain the underlying connection used by the EntityManager using implementation specific API (it's at least possible with Hibernate). This means that you can maybe fulfill your requirement without using JTA and XA at all: use the underlying connection of the EntityManager for your JDBC stuffs.
In summary:
No need to mess with XAResource
Switch to InnoDB
You can try to switch to a XA DataSource and obtain a connection with DataSource.getConnection()
You can try to switch to a XA DataSource and obtain the underlying EntityManager connection
You can try to stick with a non-XA DataSource and obtain the underlying EntityManager connection
Hope I understood your question right and that it helps.
How can i can achieve remote transaction while using Remote EJB (over RMI/IIOP or RMI/JRMP).
Is that JBoss 4.0 support this kind of transaction or should i use jotm or atomikos?
Thanks in advance
JBoss 4 is a certified J2EE 1.4 application server and thus supports client-controlled transaction which are part of the J2EE specification. In other words, JBoss provides a Transaction Manager, there is no need for a standalone transaction manager like JOTM, Atomikos, etc.
For the record, JBoss default transaction manager is based on Arjuna TS since JBoss 4.2 which is a rock solid technology.
See the chapter 4.2.3. UserTransaction Support for more details.
From jboss.org. This example is from v. 3.2 but I know it works through v. 4.0.3
There is no way to handle transactions from the client without using a TM on the client. The way to design apps is to call services on the server that handle that for you. All J2EE containers that include JTS/JTA (Ones that are more than just web app servers) will support single a two-phase transaction processing.
The client piece should be in charge of just doing presentation and possibly doing calculations as well as they pertain to displaying the data.
if you must use this strategy, go ahead use a Transaction Coordinator (TM) on the client like JOTM or Atomikos or even possibly JBOSS's JBoss transactions.