Martin told about the OSGi technology and the usage of it in big projects. He advertised the OSGi module system but also pointed on some pitfalls during design of the architecture. I was a little dissapointed, since it was a kind of entry-level talk, and its main emphasis was to recollect the importance of the service-oriented principle during system design. He pointed out the importance of loosly coupling and implicit dependency which foster maintainability of the system for many years. In the same time the fulfillment ofsuch architectural principles does not come for free.

Jan Köhnlein made a talk on DSLs in general and Xtext 2.0 in particular. The guys from itemis did a nice job in developing Xbase, a new language which can be used inside of the user DSL. For me, it is a huge step towards ubiquitous application of DSLs in software projects. Xbase give the ability to specify behaviour inside of DSLs. It is statically typed, compiles to Java, supports closures and type inference, operator overloading, etc.. – many nice features to use a little more functional programming language features in your DSL. Especially the ability to mix Java Types with Types defined in your DSL in combination with higher-order functions seems very powerfull to me.

Finally, Ralf Ebert made a very decent presentation on Git – the popular distributed versioning system. I am a big fan of Git and use it for many things i develop and saw many different presentation on those – but Ralf’s was the best one. He explained very plastically the difference in usage of Git to other versioning systems like SVN or CVS. He also showed a nice demo by showing some interesting branching and merging scenarios by switching between two users (Alice and Bob) on his machine and developing a simple web application. It was fast, precise and understandable – very nice talk.

The next Nordic Coding is planned for the August 19th, 2011.

More pictures in my FlickR set…

Please contribute to this incredible project!

My talk was focussed on the basics of CNF. After some slides on Why, What and How, I moved on to a live coding demo and coded a small CNF view inside of an trivial RCP. Everithng worked fine, until the launch – I misspelled one id in the plugin.xml, and had to resign and showed the prepaired result instead of the hacked one. If you want to read more, check out the TechJava report.

• What: Eclipse DemoCamp + Eclipse Stammtisch
• Where: Hotel East, Hamburg ( Simon-von-Utrecht-Str. 31, 20359 Hamburg, Germany)
• When: May 25th 2009, 18:00-21:00 (official part)

I’m attending. If you want to attend, make sure you find a minute to write you name down in EclipseWiki.. If you want to read more, look at the original post at TechJava…. See you on the DemoCamp.

• Singleton Beans: usefull a s a central point of the application, e.G. central cache etc…
• Async Methods: allows asynchronous execution of time-consuming methods. Especially, it is possible to abort the execution
• Deploying Beans in WARs: could be helpful for small applications
• Global JNDI-Namespace
• No interface view: simplifies the access to beans, if needed
• EJBCOntainer.getEJBContainer().getContext(): allows external initialization of bean context, which is nice for testing

Later, Adam discussed some Core J2EE patters, that become absolete with EJB 3.1 and others which are still valid. After the talk, I spoke with Adam about the OSGi as a module architecture inside JEE application, which seems interesting to me. The pictures are as usual available in my FlickR Gallery.

Yesterday, the second Eclipse Stammtisch Hamburg took place. It was nice to see the Hamburger community again. I had the opportunity to speak with Ralph about the activities in consortium and about the innovation netoworks, about German education system and other subjects. It was a very interesting discussion, even it was a non-technical one.  Later, we discussed the xText development with Peter.

As usually the rest of pictures can be found in my flickr gallery.

Details:

• When: Monday, September 1st, 19:00 CET
• Where: Roxie, Hamburg, Germany
• Directions: http://www.roxie-hamburg.com/roxieway.htm 
• Who’s comming: Doodle Poll

See you next Monday.

Since Prof. Dr. Vogt is going to retirement and leaves his position as head of the Institute of Telematics of Hamburg University of Technology a small farewell party has been organized. The most to prominent guests from the computer science community were Leslie Lamport and Manfred Broy. Leslie spoke about the benefits of usage of +CAL, a language for algorithm specification built on top of TLA+. Manfred spoke about requirements engineering and the utmost important of requirements for the quality of the software. The event has been finalized by a delicious buffet.

The pictures are available at http://www.ti5.tu-harburg.de/graphic/photos/symposium/

On Friday, I took part on the leave-taking of Prof. de Roever in Christian-Albrechts-Universität, in Kiel, Germany. Several prominent people from computer science research community spoke very kind words about de Roever, especially Amir Pnueli, who presented himself as a colleage and a competitor. Leslie Lamport also has been there, but I missed his talk that took place on Thursday. Further pictures are in my Flickr gallery…

Technorati tags: Kiel, CAU, de Roever, Pnueli, Lamport