JavaServer Faces 1.2 and JavaServer Pages 2.1 Public Review Specifications available

I'm pleased to announce the availability of the Public Review
revisions of the next release of the JavaServer^TM Faces and
Pages specifications. The Faces spec may be downloaded from < href="http://www.jcp.org/en/jsr/detail?id=252">http://www.jcp.org/en/jsr/detail?id=252>
and the Pages spec may be downloaded from < href="http://www.jcp.org/en/jsr/detail?id=245">http://www.jcp.org/en/jsr/detail?id=245>
We really want feedback! Please use our href="http://forum.java.sun.com/thread.jspa?threadID=617376&tstart=0">Forum
to share your thoughts on the specs. Or you may send feedback to
the comments alias for title="[PUBLIC REVIEW FEEDBACK]">Faces or href="mailto:jsr-245-comments@jcp.org" title="[PUBLIC REVIEW
FEEDBACK]">JSP ( title="[PUBLIC REVIEW FEEDBACK]">jsr-252-comments@jcp.org and href="mailto:jsr-245-comments@jcp.org" title="[PUBLIC REVIEW
FEEDBACK]">jsr-245-comments@jcp.org respectively) .

In this entry, I link to a comprehensive high level outline of the
changes to the spec since the 1.1 release of the Faces spec. I've
decided include changes present in the href="http://jcp.org/aboutJava/communityprocess/edr/jsr252/index.html">December
Early Draft Release as well as the current release for
completeness. Keep in mind this is a high level outline, for details,
I encourage you to read the relevant sections of the spec itself.

Before we get to the outline, here is a brief summary of the main
changes:

• Unified EL

  The expression language used in Faces, which
  was inspired by the expression language used in
  JSTL and JSP, has been generalized and extracted
  into its own top level javax.el
  package. The EL is agnostic of the technology
  hosting it, such as JSP or Faces, and is intended
  to be generally useful in the same way one can use
  OGNL in a variety of applications. Faces now has
  deprecated its internal EL in favor of using the
  Unified EL.

• New Tree Creation and Content Interweaving
  Model for Faces applications that use JSP

  While it is perfectly acceptable to use Faces
  without using JSP, many people find their
  productivity increases when using these two
  technologies together. Unfortunately, as amply
  documented by href="http://www.onjava.com/pub/a/onjava/2004/06/09/jsf.html">Hans
  Bergsten in his article at onjava.com, there
  were some integration cases that didn't work as
  expected. By changing the specification of the
  implementation of the Faces ViewHandler for JSP,
  as well as changing the JSP custom tag base class
  used by all Faces component tags, these problems
  have all been resolved.

• Integration with JSTL

  Another long standing problem was in using JSTL's
  <c:forEach> tag to contain Faces input
  components. Because JSP has no notion of a postback, it was
  not possible to apply the values correctly to the nested input
  components on postback. By introducing some new concepts into
  the EL, it is now possible to fully use
  <c:forEach> with any kind of Faces
  component. This will require a new release of JSTL, which
  will also be present in J2EE 5, along with Faces and JSP.

• Back Button issues and Multi Frame or Multi Window
  Faces Apps

  Due to a deficiency in the State Management API using Faces
  in Multi Frame or Multi Window applications presented some
  problems. The browser back button also could cause
  application state to become confused. These problems have now
  been fixed.

• Associating a message with a particular component in
  the page.

  Previous revisions of the spec didn't allow for
  dynamically including the label of a component in an error
  message for that component. New spec features now allow for
  this to happen.

The golden question, of course, where's the implementation? It's all
implemented, but the implementation of the Faces spec is only partially
available, due to the unavailability of a public implementation of the
JSP 2.1 spec. There are two reasons for this.

1. We heavily leverage the new, Unified EL, that is a
   separate spec document but, for convenience, is being
   delivered under the JSP 2.1 spec. So, while using the Unified
   EL does introduce a dependency on JSP 2.1, there is nothing
   stopping someone from implementing the EL spec outside of
   JSP.

2. In order to fix the Tree Creation and Content
   Interweaving problems (which are inherent to the old way of
   using Faces and JSP together, and therefore already implicitly
   dependent on JSP), as well as using <c:forEach> with
   Faces input components (and therefore implicitly dependent on
   JSTL), we had to make changes to the JSP spec, which are being
   delivered as part of JSP 2.1

The parts that are unavailable are those parts that a user would
encounter only when using Faces and JSP together. The parts that are
available are those parts that a user would encounter whether they use
Faces with JSP or not. Features that are unavailable at this time are
listed in gray, available features are listed
in non-gray text. Available features are present in the latest release
of the official Faces implementation on href="https://javaserverfaces.dev.java.net/">java.net which
continues to run on J2EE 1.3 containers. Note that the content in
section IV is mostly available.

Now, the outline of changes is available href="http://weblogs.java.net/blog/edburns/outline.html">here.