A REQUIRED annotated method is required to execute in a transaction but not necessarily a new transaction. If a transaction is already active then the method will execute in that transaction. If no transaction is active, a new transaction is started.

Suppose we have a stateless session bean, BankServiceBean, and we want to create an audit record every time we add a customer to the database by means of the addCustomer() method. Suppose this method invokes a method, addAuditMessage(), on another stateless session bean AuditServiceBean. This method creates and then persists an Audit entity. The Audit entity attributes are simply an identifier and a message string.

The normal sequence of events is: