September 2010
Intermediate to advanced
766 pages
18h 35m
English
So far, we’ve dealt exclusively with client-initiated requests. While this may handle the bulk of an application’s requirements, it doesn’t account for scheduled jobs:
A ticket purchasing system must release unclaimed tickets after some timeout of inactivity.
An auction house must end auctions on time.
A cellular provider should close and mail statements each month.
The EJB Timer Service may be leveraged to trigger these events and has been enhanced in the 3.1 specification with a natural-language expression syntax.
We play with timers in Chapter 19.