This is something that was quite commonly needed in Seam, in part due to the use of outjection. As 299 doesn't support outjection, you need to use the manager pattern: @SessionScoped public class Login { public User user; public Login(@New User user) { // Initialize with an empty, new, user - the "not logged in" user this.user = user; } public void login(User user) { // Log in a real user this.user = user; } @Produces @LoggedIn @RequestScoped public User getCurrentUser() { return user; } } This is much cleaner :-) -- Pete Muir http://www.seamframework.org http://in.relation.to/Bloggers/Pete _______________________________________________ seam-dev mailing list seam-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/seam-dev

Have you met producer fields yet?

Have you met producer fields yet? On Fri, May 8, 2009 at 2:06 AM, Dan Allen <dan.j.allen(a)gmail.com&gt; wrote: > I'll start by saying true, on some level that does work. And it's > reasonable. > > However, it challenges one of the core principles in Seam. You can > argue > whether that matters, but let's just follow this point. Seam > focused on > avoiding where possible the use of getter methods to access data. > Instead, > data was "pushed out" into top-level context variables where they > could be > accessed without an intermediary. The reason this was done is to > avoid > repeated invocation of getter methods. It's specially a solution that > targets JSF since JSF bombards getter methods during the life cycle > processing. Presuming that each method call is intercepted, there > is a > moderate to severe performance hit as a result. > > Looking at your case, you have reduced the number of calls to once > per > request. That's alleviates the performance problem and allows the > user to be > an independent variable for at least the scope of the request. > However, it > behaves very badly with a JSF postback. Why? When the request > begins, JSF > produces the user, which prior to login is some transient/blank > User object. > During the postback, the user logs in, effectively updating the > User object > to a managed entity. But what remains in the request scope is the > transient/blank User object. What you need is for the producer to > reproduce > at that point. > > One way around the dilemma I just cited is to redirect before > render, so as > to break your association with the current request scope and have > the user > produced again on the next request. However, it seems pretty ugly > to me to > have to redirect just to clear the result of a request-scoped > producer > method you need to reset. > > Would it be possible to have the producer method observe and event > that > would force it to produce again? That would solve most of the > cases....and > certainly it would solve this case. > > If that isn't possible, you have to change the scope of @Produces > @LoggedIn > getCurrentUser() to @Dependent, which is nothing more than an alias > for the > getter method...the point I started with. > > -Dan > > On Thu, May 7, 2009 at 7:18 AM, Pete Muir <pmuir(a)redhat.com&gt; wrote: >> >> This is something that was quite commonly needed in Seam, in part >> due to >> the use of outjection. As 299 doesn't support outjection, you need >> to use >> the manager pattern: >> >> @SessionScoped >> public class Login { >> >> public User user; >> >> public Login(@New User user) { >> // Initialize with an empty, new, user - the "not logged in" >> user >> this.user = user; >> } >> >> public void login(User user) { >> // Log in a real user >> this.user = user; >> } >> >> @Produces @LoggedIn @RequestScoped >> public User getCurrentUser() { >> return user; >> } >> >> } >> >> This is much cleaner :-) >> >> >> -- >> Pete Muir >> http://www.seamframework.org >> http://in.relation.to/Bloggers/Pete >> >> _______________________________________________ >> seam-dev mailing list >> seam-dev(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/seam-dev > > > > -- > Dan Allen > Senior Software Engineer, Red Hat | Author of Seam in Action > > http://mojavelinux.com > http://mojavelinux.com/seaminaction > http://in.relation.to/Bloggers/Dan > > NOTE: While I make a strong effort to keep up with my email on a > daily > basis, personal or other work matters can sometimes keep me away > from my email. If you contact me, but don't hear back for more than > a week, > it is very likely that I am excessively backlogged or the message was > caught in the spam filters. Please don't hesitate to resend a > message if > you feel that it did not reach my attention. > > _______________________________________________ > seam-dev mailing list > seam-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/seam-dev > > -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org