By Jonathan Bennett, uk.builder.com
Friday, July 07 2006 10:27 AM
URL: http://www.zdnetasia.com/techguide/java/0,39044898,39370280,00.htm

JBoss has joined in the AJAX game with the launch of an open-source framework for AJAX applications called Seam.

The framework, written in Java and released under the LGPL, is aimed at making developing interactive web applications easier by providing a standard set of UI widgets and back-end classes. The toolkit also contains components to make programming in a Web environment easier by taking care of session management and application workflow.

Several AJAX frameworks have been released recently, notably the Google Web Toolkit. However, as yet there's little effort to produce a vendor-neutral standard for such frameworks in any language. Without a framework like Seam or GWT, you have to write your own client-side code and server-side components to support them. However, GWT isn't entirely open source, containing one binary-only component.

Seam is based on 3.0 and needs an application server based on JDK 5.0. Extensive use is made of Annotations, introduced in Java 5.0, allowing you to specify aspects of application behaviour without large amounts of coding. The change from EJB 2.0 to 3.0 was seen by many as greatly simplifying the standard. Previous versions of EJB were criticised for being too bloated and heavy.

Other standards used in the toolkit include JavaServer Faces, and the JSR-168 Portlets API. Seam also addresses such issues with Web development as session persistence. JBoss isn't pushing Seam as purely an AJAX framework, but since it requires JSF to work, it's likely that the toolkit will almost exclusively be used in web-based applications.

Seam is the one of the first major projects to be released by JBoss since the company was acquired by Red Hat in April. Prior to the deal, the Linux distributor had tried to create its own open source application server, after talks between the two companies on bundling JBoss in Red Hat Linux foundered over how support revenues would be split.