IT Mill announces the release of Vaadin 6, a major revision of its server-driven RIA framework formerly known as IT Mill Toolkit. In addition to many enhancements and fixes, the release includes two entirely new tools: an Eclipse plugin and a preview version of a WYSIWYG user interface editor. The release of Vaadin 6 comes just months after the first stable version of IT Mill Toolkit 5. With the demanding stabilization effort of the core library behind, the company is concentrating on new features, tools, and building up the community. With the unique server-driven concept developed by IT Mill, Vaadin provides a solid base for building rich web user interfaces for demanding web applications. New Tools for Developer Productivity The Vaadin plugin for the Eclipse IDE will accelerate the work of the developers and help them build good looking web interfaces for Java enterprise applications even faster. In addition to creating new web application projects using Vaadin, it supports the creation of client-side widgets using Google Web Toolkit, making the creation and integration of custom or third-party widgets trivial. The WYSIWYG editor that also works under Eclipse is still under development, but the preview version included in Vaadin 6 release lets you see what is coming. The Eclipse plugin as well as traditional installation packages that include demos and sample code are available for immediate download at the www.vaadin.com website for Windows, Mac, and Linux platforms. In the next months, the development of Vaadin will focus on finishing the new WYSIWYG editor and developing major enhancements to the library itself. Write Java, Nothing Else Vaadin is proving to become the next major step forward in the evolution of web technologies. Built on the best Java web development concepts, Google Web Toolkit, Ajax, and server-side Java, it is a pioneering concept for RIA (Rich Internet Application) development. Using tons of widgets, developers can build rich web applications easily with Java on the server-side, much like creating regular desktop applications with Swing or AWT. There is no need to know anything about the client-side Ajax code or JSON communications working under the hood. If the versatile set of standard widgets is not enough, developers can continue coding with Java on the client-side using Google Web Toolkit (GWT). Vaadin is released under the liberal Apache License version 2 - a widely adopted license for open-source tools that allows integration with commercial applications as well as other open source projects. Live demos: http://vaadin.com/demo/ More Information and download: http://vaadin.com/

I have looked at your toolkit since the times when you used xslt. You have done an outstanding job I think with Vaadin ! (The name is cool also). But: When will Vaadin be Appengine-Ready ? Kind Regards Rusco

Actually the R&D team is working with this at the very moment to make this happen as soon as possible. You can check out the closer details on the Trac page:http://dev.vaadin.com/ticket/2835 // Jonas

Rusco, you mentioned XSLT used in version 3 released already in year 2002. I just heard of one organization that built a large ERP system for internal use in 2003 using version 3 (Vaadin was called Millstone back them): about a month ago they decided to upgrade their system to version 5.4.0. As a result their "Web 1.0" -like ERP-system transformed to a full blown RIA/Ajax application. The migration took only one day (or so they told us) . In my opinion this is fairly amazing for - large custom ERP from web 1.0 to RIA in one day... :)

The framework seems very interesting i will give it a try for sure !! But before, what about scalability ? My experience with other java ria frameworks learned me to be very careful. What about http session memory usage ? and is a vaadin application "clusterisable" meaning for instance, all all components serializable ? But congratulations, it seems very powerful !!

The memory consumption of one Vaadin session depends on the application UI size. For example serialized size of "Hello World" -like trivial application is about 10k and serialized size of Sampler, a demo application with lot of screens, is about 115k. Thus you can keep about 15.000 concurrent session in lowest end Amazon EC2 server instance (1.7G heap size). Two clustering strategies exist. I know of some production installations done on top of Terracotta, where serialization is not needed. Version 5 of the Vaadin (called IT Mill Toolkit) did not properly support serialization. Now introduced version 6 supports serialization, but of course there are no production installations yet where clustering would depend on serialization.

Good to know but, serialization is very important in clustering all above for session replication on failover.

Yes, of course, but serialization only works with sessions with no very much data. In server centric AJAX frameworks the data bound to the user session is by far more complex and bigger than the typical page based application.

Papa - it is not question of whether Vaadin should support serialization - of course it should. And it does. The real questions - why Google AppEngine should force sessions to be serialized for each request. Why not only serialize inactive sessions that have not been accessed for couple of minutes?

Actually i planned to implement my cluster within jboss. But i must admit that session replication is way too expensive and that generally i turn it off. I agree when you say that java as vendors should implements other replication algorithms ....

We should push Google to support sticky sessions and/or a transparent clustering solution like Terracotta, serializing the tree every time we change something is dirty solution and really bad for performance.

Jose, I could not agree more - serialization for each request is total waste of resources.

How about integrating popular frameworks like Spring and hibernated? I dont find much resources on this topics Thanks jsptube

How about integrating popular frameworks like Spring and hibernated?

I dont find much resources on this topics

These are are some links that may help you:

• http://vaadin.com/wiki/-/wiki/Main/Spring%20Integration
• http://blog.frankel.ch/vaadin-spring-integration

Cheers,

Nicolas