I was programming in a similar situation about a year ago, and I found the concept of application scope very useful.
Basically, the first time the application scope object is initialized, it retrieves the information from the database and then stores it. Whenever any further access is requires, it is performed to the object not the database. The tricky part comes, when the database contents change. This depends on how possible changes can occur. If the database can only be modified from within the JSP pages, then simply any JSP that modifies it, should either mark the object as 'dirty' and force it to reinitialize the data, or mark it null (there are different implications of both). If the data can be modified externally of the JSP, then you have potentially a problem. Unless you can have a threaded class which periodically monitors the database for changes, or link up anything that can possibly modify the database to notify your running program you may have problems. Hope this helps anyway, Best regards, Peter Dolukhanov -----Original Message----- From: A mailing list about Java Server Pages specification and reference [mailto:[EMAIL PROTECTED]] On Behalf Of Jerson Chua Sent: 12 December 2002 21:48 To: [EMAIL PROTECTED] Subject: Data Caching Hi, I have several drop down list in my JSP pages and their values are retrieved from the database everytime the page is requested. I found this approach to be inefficient so I'm thinking of implementing a cache for the drop down values. My question is what's the best design pattern/architecture that I can use to implement the caching mechanism? How would I be able to know if some changes were made on the database? How are guys handling this scenario? Thanks. Jerson ======================================================================== === To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com =========================================================================== To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com
