Applications using the Spring framework have always been able to run happily in GlassFish, be it v2 or v3. Now with GlassFish v3 approaching a final release, new opportunities are coming along. In a follow-up to last week's entry on managed OSGi bundles, GlassFish architect Jerome Dochez takes it a little further by implementing the GlassFish service using Spring beans and invoking it using a Java EE 6 webapp. All with no OSGi or Spring dependency whatsoever. This detailed example uses Spring's extender bundle whose role is to target the Spring container for the Spring-based service implementation, and (this is what seems to me like the most interesting part), a simple web application that can simply inject this service with a standard @Resource annotation. Of course, this is no customized version of GlassFish and the service lookup uses OSGi services and a standard Java EE annotations. No GlassFish/Spring/OSGi API required. Powerful, yet very simple.

In his recent interview on OSGi interview JavaPosse.com, Peter Kriens (OSGi Director of Technology) mentions GlassFish v3 as an example of extending a runtime without using any API specific to that runtime. It's great to hear Peter likes the work done by the GlassFish v3 team!

Modularity is important but without extensibility and manageability, GlassFish v3 would not be as exciting. Jerome Dochez, the architect for GlassFish recently posted an entry on Managed OSGi bundles. He discusses the pros and cons of deploying extensions to GlassFish as plain OSGi modules dropped into the modules/ directory or by using the familiar asadmin deploy approach. Jerome then goes on to write, deploy and test a simple OSGi bundle starting from a Java class using respectively Maven and telnet (to access the Felix Console). This entry is a follow-up to a previous one on the use of Grizzly adapters to extend the application server runtime. Jerome promises a third part to this series focusing on combining Spring, OSGi and Java EE 6, all inside GlassFish v3.

While GlassFish v3 Prelude was released in 2008, you will need to get a promoted build in order to test the features discusses by Jerome. As previously reported, the full Java EE 6 implementation of GlassFish v3 is targeting a final release in September 2009.

Good news for GlassFish and Grizzly fans: GF v3 now supports Grizzlets and other Grizzly Adapters, which means you can take your favorite Adapter and install it on the latest GFv3 build. Check out the GlassFish perspective from Jerome and that of Grizzly from JFA. You may also want to check other entries tagged grizzly and JFA's presentation on Comet in GlassFish using Grizzly, although the instructions predate this latest feature.

The web tier of GlassFish is based on the Catalina architecture (from Tomcat 4.0) that provides a number of extension points. These extensions are implementation-specific but they are sometimes indispensable. Jean-Francois's latest entry provides an overview of the different extension points, check it out. The mechanism for adding the extensions is very easy, starting with GlassFish V2 b17, which will be part of Milestone 2, later this month.