The problem with implementing conversational state with a Stack is that it is a FILO Collection. What happens if your user does not navigate linearly (e.g., jumps back 2 pages instead of 1 through a bookmark)? Why not use the container's built-in Enumeration in the Session object? Pet Store uses EJBs to maintain coversational state, and there's nothing wrong with that providing your needs justify the weight.
I have found Alur, et. al., "Core J2EE Patterns" very helpful for designing apps that both use EJBS and use only servlets and helper classes. An abbreviated snapshot of its contents can be found at http://java.sun.com/blueprints/patterns/j2ee_patterns/catalog.html And yes, Struts does this - and more. Check out the Struts user group (and archive) for details. Mark -----Original Message----- From: Vincent BUI [mailto:[EMAIL PROTECTED]] Sent: Tuesday, February 26, 2002 11:20 AM I'm looking for ideas on how to keep a kind of conversational state in a web application. I think that the servlet forum is the most appropriate place to discuss this since servlets are used for navigation control (as recommended). I try to use an MVC architecture for my transactional web application, such as one implemented on Sun site ("petstore application" for those interested). So far, I'm quite satisfied with it. But here's my problem: Users quite agree with me not to use those damned Back and Forward buttons due to problems they may cause. But then, they would like me to propose my own Back and Forward buttons in the contents of the pages, and a kind of history from the first page to the latest, no matter how many they have been through. I know that one ambition of Struts is to develop this, I don't know if it works yet. Any Struts user who can confirm this? So I intend to put a Stack container in each user's session, and put inside every page they are through. The questions are: what kind of object to put in to keep track of contents of pages they have been through? And how to implement the piling and depiling so that history is kept? Is there any recommended design pattern? My pages are mostly implemented by jsp's, or even by a collaboration of jsp's (through include tags). And I use one front controller servlet to handle requests and flows. Thanks in advance for any idea, hint, article, website, book on the subject. Vincent ===== Vincent BUI, [EMAIL PROTECTED] PS : la signature de propagande qui suit n'est pas de mon fait. ___________________________________________________________ Do You Yahoo!? -- Une adresse @yahoo.fr gratuite et en fran�ais ! Yahoo! Mail : http://fr.mail.yahoo.com ___________________________________________________________________________ To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff SERVLET-INTEREST". Archives: http://archives.java.sun.com/archives/servlet-interest.html Resources: http://java.sun.com/products/servlet/external-resources.html LISTSERV Help: http://www.lsoft.com/manuals/user/user.html ___________________________________________________________________________ To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff SERVLET-INTEREST". Archives: http://archives.java.sun.com/archives/servlet-interest.html Resources: http://java.sun.com/products/servlet/external-resources.html LISTSERV Help: http://www.lsoft.com/manuals/user/user.html
