The Spring Blog

Mark you calendars! In about two weeks, I’m hosting another Amsterdam Java Meetup; the quarterly event in the Netherlands where all people that have something to do with Java (but hey, we’re friendly; .NET guys are welcome too!) can have a chat and a drink. No technical sessions, no presentations, no keynotes, just drinks and chatting.

We have been organizing the Java Meetups for a while now and the attendance has grown from about 20 in December 2005 to about 60 or 70 last January.

So, spread the word and come join us (ah, and don’t forget, the first couple of rounds are paid for).

There a a ton of new features in Spring AOP including the AspectJ pointcut language, the <aop:*/> namespace, and the @AspectJ syntax support. But by far one of the most powerful aspects (forgive the pun) is the AOP context binding.

For example, let’s say you want to advise a method that takes a String as an argument.

public interface HelloService {
	String getHelloMessage(String toAddHello);
}

To advise this method, you’d write a pointcut that looked for a String return type, all implementations of the HelloService interface and the getHelloMessage(String) method.

Every so often I get to experience something pretty amazing about the popularity of Spring, Interface21, and our people.

Last night was one of those such moments. Rod spoke at the NY Java SIG in Manhattan. Long time NY Java SIG coordinator Frank Greco sent out an email announcing the Java SIG late on a Sunday night about two weeks ago. By Monday morning at around 9am the event had hit a maximum number of registrations of 300 (the conference room at Google gets trouble from the fire codes when they exceed 260). Effectively the Java SIG had sold out in about a business hour. I think with friends and guests the total registered list was 340. Amazingly, people were turned away at the door once the room filled to 260. For them, I am sorry they didn’t get to see Rod speak but maybe they can come down to Philadelphia for the Emerging Technologies in the Enterprise show.

Hopefully one or more open source businesses will be among the standout successes of early 21st century capitalism. However, it’s interesting to look back at one of the standout successes of late 20th century capitalism for an instructive example of one of the unusual challenges facing open source businesses.

Wal-Mart’s history is well known. The first Wal-Mart opened in Rogers, Arkansas in 1962. Five years later there were 24 stores across Arkansas. In 1968, Wal-Mart opened its first stores outside Arkansas, in Missouri and Oklahoma. Both those states, of course, neighbour Arkansas. Wal-Mart’s expansion thereafter continued to be in concentric circles around its home base, enabling logistical and cultural challenges to be overcome gradually and execution to continue to be highly efficient. Despite enormous success in Wal-Mart’s home market, wider geographical expansion has not always proven successful–as in Germany.

Last Friday I finished a training session at a client of ours. Because I had some time to kill in the hotel I was staying in, I polished the sample application I coded up during the training to post it online for the guys of the training. Usually I try to find a little sample application specific to the client’s domain to use during the training. This makes it a bit more lively instead of some of the HelloWorld examples.

This client is a big car brand, that have adopted Spring widely throughout their organization. That’s why I created a CarPlant system capable of producing cars. Below you can find a little UML diagram displaying the (rather tiny) domain model and services in the system.

A while ago, we were thinking about doing a big survey among Spring users to render feedback about parts of the framework. We’d include questions like ‘which Java version are you using’, but also ask you which Spring feature you like, dislike, et cetera.

Partially because of lack fo this, but also because for now, we don’t want to force Spring users to fill out huge surveys, we never got to actually doing this.

In the past half hour, I’ve set up a nice alternative on the Spring Framework forum. From now on, we’ll be hosting a series of polls on the forum. The polls are basically very simple multiple choice questions and the results will be available to everybody. In addition to the poll, we’ll also give some background information on each of the options.

At long last I can finally say that SPR-1484 is resolved. Opened on 20 November 2005 with 121 votes, 63 watchers, and even its own anti-ticket this issue rates as one of the all time biggies. In the last 10 minutes I’ve uploaded the maven artifacts for Spring 1.2.9 to our local repo and you should be seeing them replicated onto the central maven repo in the next 6 hours or so.

You will notice on the Spring JIRA issues such as SPR-2704, SPR-1383, and SPR-3198. What this means is that we’re not done improving our builds and and we will continue to respond to the community. In fact, we’ve got some really cool new tools that I can’t wait to show off in upcoming posts.

On the theme of application servers embracing Spring, another update. Oracle have been working on value added integration with their application server.

This is similar to what we have with WebLogic 8.1 and above in WebLogicJtaTransactionManager. The OC4JJtaTransactionManager should be used in place of the generic JtaTransactionManager in an OC4J environment, and provides the following benefits:

• Direct access to the transaction manager and helper classes without having to use
  JNDI lookups


• Auto-detection of server version to get the most out of the different transaction manager implementations in different versions


• Control over transaction isolation level: a very useful feature not available in JTA

Sun take open source seriously these days, and users seem to be starting to take Sun open source seriously too.

GlassFish was late to the party in open source application servers, but it seems to be gaining traction. And, more importantly, it actually seems to be pretty good. Various Interface21ers, including Costin and Juergen, have taken a look at GlassFish and given it the thumbs up (although we haven’t yet worked with it in production). From what I’ve heard, performance is excellent–probably substantially due to the reworked servlet engine based on NIO. The JPA implementation–TopLink Essentials–should perform well too, being based on the mature and performant TopLink engine.

Congratulations to the WebLogic team on shipping a preview of WebLogic 10, which passes the Java EE 5 CTS. It’s good to see BEA getting back to their tradition of being quick off the mark, after their aberration with J2EE 1.4.

This is interesting news for the Spring community, because WebLogic 10 uses Pitchfork internally. The Pitchfork Project is an open source project led by Interface21 and collaboratively developed with BEA that implements EJB 3.0 interception and JSR-250 injection on top of Spring. It is used inside the WebLogic 10 EJB container and in other parts of the server to meet new spec requirements, but is not tied to WebLogic. Pitchfork can be used standalone (although that’s not its primary goal) or could be adopted by other application servers.