The Transaction Manager, the Transaction Synchronization Registry, and UserTransaction

To access a UserTransaction instance, you can either look it up using the java:comp/UserTransaction JNDI name or inject it using the @Resource annotation.

If you need to access the javax.transaction.TransactionManager implementation, you can look up the Enterprise Server implementation of this interface using the JNDI name java:appserver/TransactionManager. If possible, you should use the javax.transaction.TransactionSynchronizationRegistry interface instead, for portability. You can look up the implementation of this interface by using the JNDI name java:comp/TransactionSynchronizationRegistry. For details, see the Javadoc page for Interface TransactionSynchronizationRegistry and Java Specification Request (JSR) 907.

Accessing a DataSource using the Synchronization.beforeCompletion() method requires setting Allow Non Component Callers to true. The default is false. For more information about non-component callers, see Allowing Non-Component Callers.