[ANNOUNCE] Tapestry 4.0 (final)

After nearly two years of work, the Tapestry development team is proud
to announce the next major release of the Tapestry web application
framework (http://jakarta.apache.org/tapestry/).

Tapestry is an open-source framework for creating dynamic, robust,
highly scalable web applications in Java. Tapestry complements and
builds upon the standard Java Servlet API, and so it works in any
servlet container or application server.

Tapestry divides a web application into a set of pages, each
constructed from components. This provides a consistent structure,
allowing the Tapestry framework to assume responsibility for key
concerns such as URL construction and dispatch, persistent state
storage on the client or on the server, user input validation,
localization/internationalization, and exception reporting. Developing
Tapestry applications involves creating HTML templates using plain
HTML, and combining the templates with small amounts of Java code
using (optional) XML descriptor files. In Tapestry, you create your
application in terms of objects, and the methods and properties of
those objects -- and specifically not in terms of URLs and query
parameters. Tapestry brings true object oriented development to Java
web applications.

Tapestry is specifically designed to make creating new components very
easy, as this is a routine approach when building applications. The
distribution includes over fifty components, ranging from simple
output components all the way up to complex data grids and tree
navigators.

Tapestry is architected to scale from tiny applications all the way up
to massive applications consisting of hundreds of individual pages,
developed by large, diverse teams. Tapestry easily integrates with any
kind of backend, including J2EE, HiveMind and Spring.

Tapestry 4.0 represents a significant advance over Tapestry 3.0. The
following are the most significant changes between the two releases:

* The new 4.0 specification DTDs have been simplified.
* The syntax used for binding parameters inside an HTML template
and inside an XML specification is now consistent. Both make use of
binding prefixes.
* "Friendly" URLs (that is, URLs that pack more information into
the path and less into query parameters) are built in. This makes it
easy to divide your application across many folders (reducing
clutter), and leverage J2EE declarative security along the way.
* Listener methods are much easier and more flexible; listener
parameters in the URL are automatically mapped to listener method
parameters, and listener methods can return the page name or page
instance to activate.
* Component parameters now just work, without having to worry
about "direction".
* Applications can now have a global message catalog, in addition
to per-page and per-component message catalogs. Messages not found in
the component message catalog are searched for in the application
catalog.
* Full, native support for developing JSR-168 Portlets has been added.
* Tapestry 4.0 makes much less use of reflection and OGNL than
Tapestry 3.0; partly because there are many new binding prefixes and
largely because of how parameters are now implemented.
* HiveMind services and Spring beans can be directly injected into
page and component classes.
* Tapestry 4.0 includes optional JDK 1.5 annotation support (but
Tapestry still works with JDK 1.3).
* Tapestry 4.0 debuts a new and much more sophisticated user input
validation subsystem.
* Line precise error reporting can now display the contents of
files containing errors.
* Forms can now be canceled, bypassing client-side validation
logic, and invoking an alternate listener on the server-side.
* You are no longer limited to just Global and Visit; you can have
as many application state objects as you like.
* The use of HiveMind under the covers means that Tapestry can be
easily customized to fit your needs.
* Page properties can now be persisted on the client, as well as
in the session.
* Components and component parameters can now be marked as
deprecated. Component parameters may have aliases (used when renaming
a parameter).
* The examples have been rewritten to take full advantage of
Tapestry 4.0 features, including annotations.

Tapestry is released under the Apache Software Licence 2.0.

Tapestry is distributed as a combined binary/source distribution, and
an additional documentation distribution. Tapestry may be downloaded
from the http://jakarta.apache.org/site/downloads/downloads_tapestry. cgi.
--
Howard M. Lewis Ship
Independent J2EE / Open-Source Java Consultant
Creator, Jakarta Tapestry
Creator, Jakarta HiveMind

Professional Tapestry training, mentoring, support
and project work. http://howardlewisship.com