How about registering this DropDowns in Application Context? This will ensure Singleton model anyway.
-----Original Message----- From: Hookom, Jacob John [mailto:[EMAIL PROTECTED]] Sent: Tuesday, December 03, 2002 8:36 AM To: Struts Users Mailing List Subject: RE: [OT] caching drop-down lists It wouldn't be too difficult to write your own softreference cache that would store your collections. That way, you can store as much as you want/ that the VM can handle public class DropDownCache() { private Map map; public Collection getDropDown(String key) { Collection result = null; // or use WeakReference SoftReference ref = (SoftReference) this.map.get(key); if (ref != null) { result = (Collection) ref.getObject(); if (result == null) { this.map.remove(key); } } return result; } public void putDropDown(String key, Collection dropDown) { SoftReference ref = new SoftReference(); ref.setObject(dropDown); this.map.put(key, ref); } } Then, in your BusinessDelegators, simple do a DropDownCache check, if the object's not there, hit the db and re-grab it, and store it again before returning it to the Action. -Jacob Hookom -----Original Message----- From: Jarnot Voytek Contr AU HQ/SC [mailto:[EMAIL PROTECTED]] Sent: Mon 12/2/2002 6:04 PM To: '[EMAIL PROTECTED]' Cc: Subject: [OT] caching drop-down lists In our application (and I'm sure most others) we've got a multitude of drop-down lists used for data entry. The Collections for the drop-downs are populated from the database. This doesn't seem very efficient - to hit the database for a read-only data every time. I'd like to cache this data (Business Delegate layer in our case); but I'm afraid of caching all the drop-down list Collections - I don't want to use up too much memory. I'm thinking of implementing some sort of singleton that would cache a specified number of Collections and remove the least recently used ones as new ones are requested. Has anyone implemented this sort of thing? Am I adding too much complexity (and overhead)? Do you think I should just cache them all - after all, I'm not sure that there will actually be so many as to use an inordinate amount of memory? Just thinking out loud... --Voytek Jarnot -- To unsubscribe, e-mail: < mailto:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: < mailto:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> > ------------------------------------------------------------------- This email is confidential and intended only for the use of the individual or entity named above and may contain information that is privileged. If you are not the intended recipient, you are notified that any dissemination, distribution or copying of this email is strictly prohibited. If you have received this email in error, please notify us immediately by return email or telephone and destroy the original message. Thank you. - This mail is sent via Sony Asia Pacific Mail Gateway. -------------------------------------------------------------------
