Jazoon 2008 roundup

So the Jazoon 2008 is over and it was great fun. After my talk on the first conference day I relaxed and was enjoying the rest of the conference. In my book the presentations given by Joshua Bloch, Principal Engineer at Google, were the conference highlights. His presentation are not only informative but also entertaining. The opening sessions and keynotes are available as videos from Parleys, check them out yourself.

Most presentations, including mine, are already available for download from the Jazoon website.

Jazoon day 1 wrap-up

The first day at the Jazoon Conference is over. The Opening Sessions were really interesting. Martin Odersky started out with a talk on Scala which keeps to be the new thing to check out. Simon Phipps gave a really impressing talk on free software in the market, how to bring free software from niche to mainstream.

My own talk went quite well. I was less nervouse than I had expected, so it went like clockwork. Although I had quite a lot of slides I did not exceed the time limit. The slides will be available from the Jazoon homepage after the conference and I made the example sources avaliable from my private homepage.

A thrill of anticipation

I'm sitting in the Work Area at the Arena Flimcity where the Jazoon 2008 is going to take place. The Opening Session will start in about an hour. Web 2.0 technologies are quite a big topic here. Web developement, Ajax and all the frameworks around it get a lot of attention. There are three talks on GWT, one by myself :-)

Javapolis 2007 roundup

I'm back from the Javapolis 2007 conference. I had a great time over there in Antwerp. I have attended many interesting talks about Java, JSRs, GWT, Scala, methodology, testing and many more Java related topics. The Java Puzzlers by Neal Gafter and Joshua Bloch was the best (fun, interactive and informative) talk in my opinion. During and between the talks there were many discussions about different JSRs and the future of Java in general. To listen and talk to some of the greatest minds in the Java world was really enlightening. Another highlight was the Java Posse Live session, if you don't yet now the Javaposse podcast you have to check it out!

I have also met some people from the GWT community. Maarten Volders (Thanx for lunch!), Luc Claes and the two speaker of the Google Web Toolkit talk Didier Girard and Dick Wall.

I really hope I can be there in 2008!

Experiences with Chronoscope

The Chronoscope online documentation is a bit thin at the moment. I am sure the guys over at Timepedia are working on the documentation, so this is likely to be improved quite soon. Here is a list of things that stroked my attention while using Chronoscope, things that are not documented but one should be aware of. Note that the Traceurl Google Gadget is a plain JSP and I have not been using the GWT or JavaScript but the Microformats version of Chronoscope instead.

• Apparently the missing IE support is issue number one. On the Chronoscope Group Ray Cromwell said that they are 'targeting IE support in the next month or so.'


• Traceurl.com supports two languages (English and German) and the Traceurl Google Gadget even three languages (English, German and French), thus a proper solution for internationalization is very important for me. At the moment Chronoscope's I18N/L10N support is weak, respectively close to non existent. Ray Cromwell comment about I18N was 'We plan to support it. [..] I view I18N/L10N very important, and we will most likely be using GWT's builtin L10N features to do this efficiently.'.


• Related to the currently missing internationalization support is the problem that the axis identifiers are not interpreted correctly. Using microformats the first row of the THEAD element specifies the axis labels. The label for the value label is set correctly, but the name of time axis is ignored. Setting the German word 'Zeit' instead of 'Time' the chart is still displaying 'Time.'


• In the first attempt I used a HashMap to keep track of the number of accesses per day. With the effect that the generated TBODY element contained unsorted rows. That does not work, Chronoscope needs its input to be sorted by time.


• The second thing I realized is that the input should not have gaps. The time line has to contain all dates, setting the value of the dates without accesses to zero. Otherwise Chronoscope kind of interpolates the missing values, which is obviously wrong for my accesses per day use case. For example, say we have the date 06/09/07 with 12 accesses and the date 06/11/07 with 6 accesses to a traceable URL, not setting the 10th to 0 will result in a wrong graph with an interpolated value of 9 accesses for the date 06/10/07. That is not necessarily an error, but just the way Chronoscope handles its input and something the developer needs to be aware of.

The latest release is a beta version and I am sure things will be improved with upcoming versions. The above list is not meant as criticism, but as assistance to people who want to get their hands dirty with the beta release. I am a programmer myself, so I am well aware of the tremendous amount of work that went into Chronoscope. Chronoscope rocks and I am going to use it further on. In one of the next post I will give you some insight into my implementation. A short cook-book style abstract to get you (in case you are a developer) up and running with your own Chronoscope time series chart.

Time series visualization in Google Gadget

I included the access time series visualization into the Traceurl Google Gadget. There is a new icon right next to the Google Map operation in the Traceurl Google Gadget. Click on the new icon and a new window with a time series chart for the respective traceable URL is displayed.

As mentioned in the previous post the Chronoscope platform does not yet support Internet Explorer, using IE you are getting a blank page. For this reason I'm not going to add the time series functionality to the Traceurl.com main application for now. I'll keep you up to date about future progress.

Time series chart

Okay, I finally got some new functionality up and running. It is not yet fully featured, because it relies on a beta version framework. The point of the new functionality is to visualize the accesses to a traceable URL on a time series chart. This is done with the help of the Chronoscope platform. Timepedia announce the first beta release of Chronoscope a couple of days ago and I have been playing around with it over the last weekend. The first shot of an access time series looks like this:



One of the coolest feature of Chronoscope can not be seen on the screenshot, it is the possibility to zoom and pan within the chart. Have a look at the demo page to see a live version, is really impressive! Chronoscope currently lacks IE support, thus the charts only work on Firefox, Safari and Opera. I hope they can fix that soon, because that is kind of a show-stopper :-(