11.5.2. Lifecycle of a JTA Transaction

To begin a transaction, your application obtains an instance of class UserTransaction from JNDI or, if it is an EJB, from an annotation. The UserTransaction interface includes methods for beginning, committing, and rolling back top-level transactions. Newly-created transactions are automatically associated with their invoking thread. Nested transactions are not supported in JTA, so all transactions are top-level transactions.

Calling UserTransaction.begin() using annotations starts a transaction when an EJB method is called (driven by TransactionAttribute rules). Any resource that is used after that point is associated with the transaction. If more than one resource is enlisted, your transaction becomes an XA transaction, and participates in the two-phase commit protocol at commit time.

In the next step, your application performs its work and makes changes to its state.

When your application has finished changing its state, it decides whether to commit or roll back. It calls the appropriate method. It calls UserTransaction.commit() or UserTransaction.rollback().

After the commit or rollback completes, the transaction manager cleans up its records and removes information about your transaction from the transaction log.