I am just about to hear from Rob Harrop on building modular web applications using OSGi.
RFC-66 is a specification for standardizing the installation and management of war files in an OSGi environment.
So far it has been a demo oriented session. Rob is doing some live coding, building and then deploying it on the server. He is using this system to explain the various details involved in web application development in an OSGi environment.
I attended the agile architecture and patterns session in the morning and then the SPEL (spring expression language) by Craig Walls. SPEL surely provides some cool convenience features. Currently I am in Costin Leau and Mark Pollack’s Java EE 6 and Spring session.
Java EE 6 web profile:
Servlet 3.0:
JSR-303, the bean validation spec is integrated into spring. Validation can be applied to any spring bean.
EJB 3.1
EJB 3.1 Lite
Value of EJB 3.1 Singletons
Long overdue: statup/shutdown hooks.
Finally an EJB session bean without pooling. No pooling overhead imposed anymore.
EJB 3.1 from a Spring perspective
EJBs remained tied to a dedicated EE6 container. But container can be embedded and added additional deployment model – .war file.
Easy access to EJB session beans from within Spring.
Spring Framework != EJB (Lite) container.
Just influences some Spring features – Spring 3.0 @Async etc.
EJB 3.1 singletons resemble Spring singleton beans with different concurrency defaults.
JSR-330 is an “extensible DI API to maximize testability and maintainability of Java code”. JSR-330 requires only Java SE and not dependent on any external containers. Provides a common understanding of injection semantics. This spec is already supported in Spring 3.0.
JSR-299: Initially it was web beans. Glue between JSF and EJB and hence the web name.
Bottom line is that Spring is actively tracking Java EE 6.
In the morning I attended two spring MVC oriented sessions one presented by Keith Donald on an overview of the spring web stack. New Spring MVC introduces a lot of annotation based controls. Keith went through different examples as to how these new features can be implemented.
JSR-303 – standard bean validation specification. Spring MVC provides a JSR-303 implementation (is currently available through a milestone download). Seems like Hibernate provides the reference implementation for this.
Jodatime is a better API as an alternative to java.util.Date.
Spring Javascript is Spring’s Ajax integration library. It is built on top of the popular Dojo toolkit. It provides among other features support for opening modal dialogs. Doug Crockford has a good Javascript book: The good parts.
Sprng webflow allows the user to not to be concerned with low level HTTP session management details.
Then I went to Arjen Poutsma’s talk on REST based web application architecture. It gave a good introduction into REST in general and how Spring 3.0 leverages on top of it.
In the afternoon, there was a good session on introducing Spring ROO. It seems very promising as a quick enterprise environment setup of project environment.
There was one more interesting session on various DI styles that we can use with Spring. JSR-330 is coming which deals exclusively with dependency injection in general in Java regardless of the framework that you are using. There are internal/external, implicit/explicit dependency injections.
Finally I attended Adrian Colyer’s keynote. Even though his talks and keynotes were extremely good and deeply technical in the previous years, this year it was more formal and business oriented with a lot of Vmware and cloud computing stuff.
Over all, the day went well and the sessions I attended were interesting.
It seems like Craig Walls attended almost all the sessions I attended and he blogged on a day 2 wrap up as well (a much more detailed one than this!!).
I am in New Orleans this week attending Spring one . The main event on day one was the key note address by Rod Johnson, the founder of Spring Framework. Rod went over the timeline from 2003 on how Spring Framework was evolving and changed the Java EE landscape. He touched on a number of Spring-centric technologies during the keynote such as spring-integration, spring-blazeds, Grails, tcserver, Springsource tool suite etc. There were couple of demos during the key note as well. Spring-integration/blzeds and grails demos looked interesting. They are definitely worth to take a closer look at.
