myfaces-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Andrew Robinson" <>
Subject Re: Component Binding issues
Date Mon, 09 Apr 2007 21:01:48 GMT
They can also cause issue with duplicate IDs if the ID of the bound
component is auto-generated

On 4/9/07, Simon Kitching <> wrote:
> Phanidhar Adusumilli wrote:
> > Section 3.1.5 of the JSF specification, recommends not use component
> > bindings at session/application scope.
> >
> > What are the issues in binding components to manged beans at
> > session/application scope?
> A UIComponent object has references to its parent and all its children.
> Therefore if you store a reference to any UIComponent in a session-scope
>   bean then the entire component tree for a particular view is kept in
> memory.
> Session-scope backing beans are generally a bad idea anyway; they waste
> memory as they are created when a user accesses some view then hang
> around until the user logs out even if the user never revisits that
> view. If this object has a reference to a UIComponent, therefore keeping
> an entire component tree in memory too (see above) then that's even
> worse. There are some cases where session-scoped beans are appropriate
> but normal "backing beans for views" should be request-scoped wherever
> possible.
> Referencing a component from an application-scope bean (ie one shared
> between users) just makes no sense at all. Components are not
> thread-safe but application-scope beans are shared between users and
> therefore must be thread-safe.

View raw message