There are two use cases where we DMS will use the UserTransaction.
1) When your assembler has "use-transactions=true", and you commit a change or batch of changes, the DMS code will start a transaction before calling your createItem, updateItem, and deleteItem methods. If any of those get an error, the transaction is rolled back and all of the changes are put back into the uncommitted list on the client. If they all succeed the transaction is committed and the changes pushed to other interested clients. 2) If you use the DataServiceTransaction api to push changes from the server, when you call begin you can pass in a value of "true" which causes the DMS stuff to start a JTA transaction in that call. When you call commit, the JTA transaction is committed if the setRollbackOnly call was not made. This is just a convenience if you happen to have some JDBC code which is updating the database. You want to both commit those changes and push the changes to other clients or rollback those changes and cancel those changes. For 1), when you are also using Hibernate, the hibernate assembler will register a hibernate current session context class. The goal of this class is to ensure that we create one hibernate session for each JTA transaction we create for DMS and commit/roll them back in sync. Going forward I'd like to offer another way to do this so that we can more flexibly integrate with other ways of using hibernate sessions. Jeff ________________________________ From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of den.orlov Sent: Wednesday, December 12, 2007 2:10 AM To: flexcoders@yahoogroups.com Subject: [flexcoders] Flex Data Management and container's UserTransaction As I understand Flex Data Management Services require that application container provide UserTransaction for it. But I can't find any guide about how FDMS uses it. I was completely confused when I checked several tutorials that used FDMS+HibernateAssempler+Spring or FDMS+hand written Assempler+Hibernate+Spring. That tutorial http://blogs.adobe.com/mtg/2006/08/my_first_hibernate_enabled_fle.html <http://blogs.adobe.com/mtg/2006/08/my_first_hibernate_enabled_fle.html> specify that Hibernate's SessionFactory use datasource not tied to global transaction manager. This tutorials: http://devblog.ezmo.com/2007/05/29/using-flex-data-services-with-spring- and-hibernate/ <http://devblog.ezmo.com/2007/05/29/using-flex-data-services-with-spring -and-hibernate/> http://iamjosh.wordpress.com/2007/11/08/building-a-livecycle-data-servic e-application/ <http://iamjosh.wordpress.com/2007/11/08/building-a-livecycle-data-servi ce-application/> don't specify that SessionFactory should use global transaction scope for Session and use local transaction management. So what's the purpose of FDMS to have reference to container's UserTransaction? Den
