The commonj api enables concurrent programming of ejbs and servlets within a j2ee application. this api is also known as timer and work manager api.

the commonj api contains the following components:
- timer api:
the timer api allows applications to schedule and receive
timer notification callbacks for a specific listener defined
within an application. timers allow you to schedule and
perform work at specific times or intervals.
- work manager api:
the work manager api allows an application to prioritize
work within an ejb or servlet. applications can
programmatically execute multiple work items within a
container.