September 2010
Intermediate to advanced
766 pages
18h 35m
English
As we’ve seen with message-driven beans, a client request is not the only way to start a business taskflow. In addition to listening on incoming messages like MDB, events can be fired based on some timed criteria. EJB handles this via the Timer Service.
EJB 3.1 has seen significant advancements to the bean provider’s
view of the Timer Service with a completely revamped natural-language
syntax. This example models a credit card processing operation, which at
the beginning of every hour will process all queued transactions.
Scheduling the job is done both programmatically via the javax.ejb.TimerService API, as well as
declaratively via the @Timeout and
@Schedule annotations.