wood burning stoves 2.0*
The moose likes OO, Patterns, UML and Refactoring and the fly likes notification pattern Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login

Win a copy of Android Security Essentials Live Lessons this week in the Android forum!
JavaRanch » Java Forums » Engineering » OO, Patterns, UML and Refactoring
Bookmark "notification pattern" Watch "notification pattern" New topic

notification pattern

Paul Celona

Joined: May 20, 2004
Posts: 15
I am trying to design an appllication that using dynamic notification to clients upon data store updates (i.e. background threads a,b & c update an event database, and then another ejb notifies gui Z that updates have occurred and either provides the updates or indicates that updates have occurred. Gui Z (could be stand alone java app or applet) then calls an ejb to retrieve the updates for display). The general purpose is to eliminate continually polling the database for new updates.

Is there a design pattern for client registration, update notification, etc for this. I had envisioned using message ejbs for this.
Mani Ram
Ranch Hand

Joined: Mar 11, 2002
Posts: 1140
Check the Observer pattern.

Quaerendo Invenietis
Paul Celona

Joined: May 20, 2004
Posts: 15
Thanks for the reply. Is there an example implementation using jms somewhere?
Jignesh Patel
Ranch Hand

Joined: Nov 03, 2001
Posts: 626

Is there an example implementation using jms somewhere?

There are plenty of there. Use google.
Stan James
(instanceof Sidekick)
Ranch Hand

Joined: Jan 29, 2003
Posts: 8791
JMS has a publish-subscribe model that is made for just this. The Sun JMS Tutorial should be a good starting point. Gregor Hohpe has a great collection of messaging patterns.

A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
Paul Celona

Joined: May 20, 2004
Posts: 15
Looking on the net I haven't found a design pattern that pulls both JMS publish/suscribe and notification/registration. I've seen the later for ejbs, but not incorporating JMS. Short of buying the eai patterns book, is there another resource out there?
I agree. Here's the link: http://aspose.com/file-tools
subject: notification pattern
Similar Threads
Transaction rollback
Making JTable updates threadsafe and keeping GUI responsive
Repainting JInternal Frames
WebLogic Not reading an updated value in the same transaction
Composite Entity Pattern