I've heard of hidden frames, but never seen them. (that's not a pun). could the hidden frame contain HTML that has a metarefresh of say 1 minute. The HTML is generated by a JSP. This JSP would track if there was a change. If there wasn't a change, just output a blank body with the meta refresh. If there *was* a change though, output a page that has some javascript onLoad stuff that will pop open a new window that contains .... * a static message that something changed * custom message that 'XYZ' changed. The popup page would then be driven by a JSP
> -----Original Message----- > From: Shapira, Yoav [mailto:[EMAIL PROTECTED] > Sent: Wednesday, August 13, 2003 11:13 AM > To: Tomcat Users List > Subject: RE: Question about Notify all online user > > > > Howdy, > > >How to implement notifying all online user when the record > in database > has > >been changed? I am using Servlet and JSP to build a small > Supply-Chain > >system running on Tomcat with MySQL. > > Cool design question ;) You probably can't do it immediately > on change, but on the next page the user loads after the > change. Here's an > approach: > > - Have a Filter mapped to all requests (url-pattern /*) that > polls the DB or listens for the DB change event from another source. > > - Have a servlet that displays the contents of this change, > let's call it ServletA > > - When the DB changes, the filter is notified and does the following: > - Puts a "notified" attribute with value "false" in > every incoming request > - Gets a RequestDispatcher for ServletA and includes > its contents in the response > - Sets the "notified" attribute to value "true" after > chain.doFilter, i.e. on the response's way back to the browser > > It's just an idea, doubtless others will have a different take ; > > Yoav Shapira > > > > This e-mail, including any attachments, is a confidential > business communication, and may contain information that is > confidential, proprietary and/or privileged. This e-mail is > intended only for the individual(s) to whom it is addressed, > and may not be saved, copied, printed, disclosed or used by > anyone else. If you are not the(an) intended recipient, > please immediately delete this e-mail from your computer > system and notify the sender. Thank you. > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
