Session title: Programming the Semantic Web with Java
Speaker: Taylor Cowan, Travelocity

Taylor claims to quote Niel Ford (prior keynote): “The best way to predict the future is to create it”… and doesn’t appear aware that he’s actually quoting Abraham Lincoln.

Taylor shows a couple of sites which exhibit the semantic web, one of which is Yahoo.

Then demo’s GeoSPARQl which enables semantic-style queries.

Then contrasts RDFa (a way of embedding RDF in XHTML) with Microformats, the latter being more complex to parse. With RDFa you can use a single format and hence require a single parser. With Microformats you a parser for each format.

Technically, everything identified by UDI, all data as canonical RDF, RDFS provides a schema, OWL provides additional meaning, SPARQL queries semantic web data, RDFa encodes RDF within XHTML.

Speaker then contrasts the RDF Triple Store vs. the Relational DB approaches to persisting semantic web data and notes that RDF is not XML but rather a way of structuring data as a directed graph. In this graph nodes are nouns; axes are verbs.

For the record: Triple = Subject, Verb, Object

The concepts in a semantic declaration can be represented sequentially using N3.

Similarly, the Java API JENA can also be used to model semantic relationships.

Using an inferencing engine new relationships can be derived automatically e.g. the explicitly declared relationship “Java is the primary topic of Jazoon” (after interence) automatically results in a new relationship “Jazoon has Java as the primary topic”. Pretty neat!

One of the major pain points with JENA: Having to create unique URL’s for every entity.

Taylor then describes a bean helper mechanism “JenaBean” (which I understand he created and is hosted at jenabean.googlecode.com) which (he claims) makes working with JENA somewhat easier.

Finally some words on tooling:
Triple stores: JENA, Sesame OpenRDF and Mulgara are all Java-based.
Java binding tools: JenaBean, Jastor, Owl2Java, Elmo.

During Q&A Taylor notes that triple store scalability is often a big issue; thinks that commercial solutions such as Oracle’s will not suffer from this problem.

From the perspective of a non-expert in Semantic web (i.e. myself), this was a valuable, quick introduction to a deep subject. Good stuff!

Links:
http://thesemanticweb.com
http://twitter.com/tcowan

‘Groovy Usage Patterns by Dierk König’ is currently being showcased on the ‘Technology’ page on SlideShare. Enjoy!

Keynote title: The Changing Nature of Enterprise Java Application Development
Speaker: Adrian Colyer CTO SpringSource

Adrian – perhaps principally of AspectJ fame – begins by stating that we live interesting times and that “seeds of change” are present… which leads naturally enough to a rain-forest metaphor.

To cut a long story short: New stuff starts out as a seed, some of this stuff rises and becomes well established… whereas much of it dies out at some point on the way up. Assuming my interpretation of the symbolism is on the mark.

A picture of the sun setting over the rainforest… represents Sun “moving on”. And the metaphor continues… but strangely I find my interest in it is waning…

Adrian cites Java 7′s improved for support new languages, plus the proliferation of new languages (Groovy, Scala, Erlang, JRuby, Clojure, Jython, Ruby) as one of the significant new developments. And questions which one of the new languages will dominate over the coming years…

And initially picks Groovy, Clojure, JRuby and Scala because they are designed to work on a JVM.

A comparison of Java versus Groovy ensues, with emphasis on Groovy conciseness.

The challenges posed by concurrency are mentioned, and Clojure’s “immutability by default” and Scala’s built-in actor model are cited as a ways of addressing them.

The speaker drops Clojure from his list of candidates because he feels the Lisp-inspired syntax of Clojure too radical a leap from Java’s syntax and the C-legacy/culture.

Eventually he gives Groovy the edge because of its super-tight two-way integration with Java… and then is kind enough to admit his (or his company’s) bias in this matter.

Next up: A monolog on the various application frameworks, and acknowledges both the power and the complexity of the new programming environment. He recalls the classic terminal application to reinforce the point that times have changed radically. Can’t disagree with that!

The final message: “The future is coming!” which for me definitely means a very strong coffee.

Conclusion: A well delivered presentation, rather too drawn out and too long on metaphors. Nevertheless, an opportunity to reflect a bit about the strange, changing ocean in which we IT geeks are immersed. Hey… I wonder if I can develop this metaphor and use it in my next presentation?

Now I’ll be the first to admit that I’ve had my issues with Java-the-language over the years. When it came to the lack of support for Design by Contract, for example, I recall thinking to myself back in the late 90s “if I ever meet James Gosling personally, I’m gonna give him a piece of my mind!”

Well, at long last I did finally get a chance to meet James “the father of Java” Gosling (which I guess makes him the grandfather of Groovy, Scale, JRuby and subsequently the great grandfather of myriad other life-changing innovations.) And guess what… I did not give him a piece of my mind.

This was because immediately following the Java Rookie event JG was simply too forthcoming, too attentive and too downright chilled when I approached him with a view to chatting about matters more constructive than simply what Java lacks or cannot do.

Here I am in chat mode with The Man:

Here are some other members of the Canoo/Jazoon’09 team in completely natural poses:

So thanks James for gracing Jazoon’09 with your presence. You made a great conference even greater. We wish you a pleasant journey home!

This special event at Jazoon ’09 (sponsored, incidentally, by Canoo) gives three young Java developers the opportunity to give a presentations on applications they have developed. An expert panel will offer judgments on the quality of the presentation and the value of the presented application of Java technology.

The candidates:

•    João Arthur Brunet Monteiro: “DesignWizard: A Tool that Gives Support to Automatically Check Your Code Against Design Rules“. Read the abtract!

•    Bettina Polasek: “Modern Times in Software Quality Engineering“. Topics: Testing tools, Software engineering lifecycle, show cases. Read the abtract!

•    Deni Lukmanul Hakim: “Showing a real 3D with JavaFX“. Topics: Integration and interoperability, Rich user interface technologies. Read the abtract!

On the panel:

• Dierk König: Author of “Groovy in Action” and Groovy & Grails committer
• James Gosling: Father of Java
• Bela Ban: Lead for the JBossCache project
• Corsin Decurtins: Jazoon Program Committee

João from Brazil gave a classic rookie pitch, meaning really natural, student like and above all free of product advertisement. Despite obvious nervousness, a very likable personality came through. The subject matter of automated checks e.g. dependencies, is as relevant as ever.

The Swiss/Hungarian presentation was well executed but very traditional in format. The speaker presented a number of slides which were in many cases text-heavy. This ALWAYS detracts from the actual speech. From my perspective, the reoccurring appearance of the candidate’s employer’s logo (an obvious advertisement) left a strange taste in the mouth. 

On the content, the speaker is clearly very fixed on the idea of producing software in a production-line manner. We know from experience that this is not always possible or effective, which is how the agile movement was born.

Deni the Indonesian presentation didn’t suffer from too much text but did suffer from what sounded like too much like a JavaFX sales pitch. It became obvious that he loves to work for Sun and so everybody got a 15 minute product pitch. Unfortunately this left just 5 minutes, what was way too short for his project details – the main point of the talk.

Canoo’s Roland Zigerli attempts to gauge  the degree of positive feedback from the audience by means of decibel measurement… but in the end it falls to the judges to make the final decision. And the decision is:

• 1st place: João from Brazil
• 2nd place: Bettina from Hungary/Switzerland
• 3rd place: Deni from Indonesia

Congratulations to all entrants!