Jazoon: Data Driven Applications

25. June, 2008

Not one of my favorite talks, to be frank. Brian Sletten tried to explain how we would write less code in the future because data would become more important. Seeing is believing and I haven’t seen nothing, yet.

He has a few good point like that we should be able to recall data sets which we created with Web 2.0 sites (kind of like bookmarks on steroids that can save the state of the web 2.0 app as you bookmark it). Also, that the semantic web will make a lot of things possible and happen.

I buy that. But on the other hand, we don’t even have a decent UI framework for Java yet and that’s eight (8) years after Swing came out. This sure looks promising; I just wonder if I will be still around when it starts to deliver and companies get the CPU power and network throughput to really run all their data through RDF converters. And see the result before you get downsized.


Jazon: Building DSL’s

25. June, 2008

Neal Ford‘s talk about DSLs and how to create them in static and dynamic languages (Java and Groovy in this case) was very interesting because he clear up the fog around DSL’s a but, why they are great and when they help. Basically a DSL is “jargon”. It is compact code that allows you to express much more tightly what you want than any “general purpose” language (“one site fits all” actually makes everyone look ridiculous).

Remember that old OO promise to allow to mirror the world in a programming language, to allow to model the code after what the customer had in mind? Turns out, that OO was … nah, not lying … it was just overselling itself because customers don’t think in objects or models. They think jargon. And DSL’s allow you to make a compiler understand jargon. That’s even possible with Java even though “Java is like taking to a retard”: You always have to repeat yourself to make sure that the stupid compiler gets what you want (pun intended).

A DSL is not to be confused with an API. An API uses explicit context like “obj.setThis(…); obj.setThat(…);” etc. Here “obj” is the context and “setXyz()” is not meaningful without knowing the object we’re talking about here. A DSL, on the other hand, is all about context and context is implicit. It goes “obj.should(…).allow(…).this(…)”. An example is hamcrest: “assertThat(theBiscuit, is(myBiscuit));” Reads fluently, compact code, and it’s obvious that “is(myBiscuit)” should be compared to “theBiscuit” in some way.

The handouts of his presentation are available from his homepage but without his witty remarks. A pity but still worth to check out if you want to see just how far you can push Java to get code that your customer might understand.


Jazoon: Rich GUI development with Java

25. June, 2008

If you ever tried to develop a nice you with Java, you’ll know the pain. Swing: Old, steep learning curve, unweildy widgets. SWT: Nice, good learning curve, “which JAR’s do I need, Sir?” and who puts that DLL in my search path. There might be other contenders but I don’t even remember their names.

So the guys at Canoo faces the dragon and chipped a few scales off it. As Bruno Schäffer said in his talk:

Developers should focus on the what and not how.

They used Swing, some components from SwingX, JGoodies Smart Client and Jemmy for testing for the UI and something called c3pO for JDBC connection pooling to build a smart client. openArchitectureWare was used to generate a model editor for the data model, so they could generate the DAO classes for that efficiently.

Their application is split into modules but they don’t use OSGi or any other module framework out there because they got in their way, it’s just good old, traditioal loading on demand from the classpath. I can relate to that. OSGi is so great and stuff … but it somehow lost contact to the base. It’s just eithet not flexible enough or not simple enough for me to understand and use.

Good talk but less product placement for your company next time, Bruno.


Jazoon: openID

25. June, 2008

Robert Ott showed off openID. If you wondered about these strange links which start to pop up all over the web near the login buttons, openID is a way to register yourself once at a place you trust and then use that to login elsewhere.

The idea behind openID is that you click on the link, the web site passes you on to an identity Provider which can use any means to make sure you are you and then give that confidence back to the original site. See the openID.net website for details.

The cool thing about openID is that you just have to manage a single identity and use that to log in into various services on the net without giving all of them the same password (and thus make you very vulnerable agains attacks). The main problems which openID doesn’t solve is stalking and spamming.

openID makes stalking easier because you have to enter your openID at every place you want to log in to. Same id means same person. There are talks in the openID community to allow a person to have more than one ID and still use the same identity provider but there is nothing definite, yet.

Also, openID doesn’t protect against spammers. It might help, though, because of two things: a) You can black list identity providers which allow spammers and b) you can send the police to the other identity providers which will hand over the real identity of the person behind the openID to the authorities on court order. So this might help in the war against forum spam, we’ll see.

All in all, a good talk.