| Daemon Factory can create new DaemonService, which runs on seperate
background threads. One can use these DaemonService to handle background
clean up task by implementing Serviceable and subscribing to a DaemonService.
A DaemonService is a background worker thread which does asynchronous I/O and
general clean up. It should not be used as a general worker thread for
parallel execution. A DaemonService can be subscribe to by many Serviceable
objects and a daemon will call that object's performWork from time to
time. These performWork method should be well behaved - in other words,
it should not take too long or hog too many resources or deadlock with
anyone else. And it cannot (should not) error out.
The best way to use a daemon is to have an existing DaemonService and subscribe to it.
If you can't find an existing one, then make one thusly:
DaemonService daemon = DaemonFactory.createNewDaemon();
After you have a daemon, you can subscribe to it by
int myClientNumber = daemon.subscribe(serviceableObject);
and ask it to run performWork for you ASAP by
daemon.serviceNow(myClientNumber);
Or, for one time service, you can enqueue a Serviceable Object by
daemon.enqueue(serviceableObject, true); - urgent service
daemon.enqueue(serviceableObject, false); - non-urgent service
See Also: DaemonService
See Also: Serviceable |