Using Transactions with Session Beans
The EJB container provides support for transactions as one of its primary services. The WebLogic EJB container makes use of the WebLogic Server's Java Transaction API (JTA) implementation.
In session EJBs, there are two transaction possibilities: bean-managed transactions and container-managed transactions. The transaction-type tag in the ejb-jar.xml selects the transaction type. For example, <transaction-type>Bean</transaction-type> would use bean-managed transactions.
Container-managed transactions free the bean writer from explicitly coding calls to begin or commit a transaction. Instead, the EJB writer declares transaction attributes in the ejb-jar.xml deployment descriptor. ...