Łukasz Lenart – “Nie samym kodem programista żyje”

Łukasz’s presentation was not a technical one this time. He talked about how to be/become an effective programmer. A nice tip he noted was to carry a notebook and note your ideas in it – i sometimes try to but did find myself forgetting some “amazing idea” due to the lack of discipline in carring such notebook (yeah, an paper-notebook… :-)) so it’s definitely something worth reminding. He also talked a little about Kaizen, ZenToDone and the Pomodoro Technique which all kinda share the same idea but explain it a little bit differently. I also was quite happy to find out that I’m not the only one that gets slown down in development when actually being in the company – with lots of stuff happening around me. Admit it – we all work more productive when there’s noone bugging us ;-)

The most notable tips where the “alone-zone” (as explained in REWORK (good book, I recommend it)) which is really great and I love it, but sometimes it’s hard to enforce – coding is usualy team work, ain’t it..? Using multiple desktops – and monitors at best, to seperate your work space from fun space. Cutting oneself off from the internet is, while extreme, very effective by the way. I noticed it quite a few times – there’s simply nothing distracting you – same goes for anything that might take your attention. By the way, I’m not really convinced about Pomodoro – what if you get into an v. nice flow and then the pomodoro snaps you out of it? I guess it may be more targeted at people working at bigger companies – not as myself in an small nice team and nowadays, mostly from home.

All in all he warmed up the audience perfectly and let’s hope some of theese tips help us become better programmers… :-)

• //TODO: watch on parleys.com
• //TODO: download slides
• download video

Konrad Malawski – “Git (tak. po prostu.)”

The PJUG guys asked me to tell a little about git and I happily agreed to do it – thus, my first “public presentation”. Firstly I’d like to explain why the slides where so “weird”. It’s because I wanted them to be something like an “break”, and most of the session was live terminal typing. They were all hand drawn by me and my girlfriend, then scanned and recoloured in GIMP. Took a few evenings to prepare them, but I hope they where quite memorable, fun, and did point out the important aspects of what the next topic would be about – an 3 headed dragon as symbol for lots of HEADs in an git repo etc… ;-)

Click to show presentation

I’ve been preparing the flow of all examples before but during the presentation I missed out a few steps and made a some stupid mistakes (see my previous git post on this blog ;-). Well, it wasn’t anything world breaking I guess and I’d really like to thank the audience for such great support. We strayed a little of the path I’ve prepared sometimes, but that’s ok as it was interesting to interact with the audience during an presentation – not just stand there and “praise git to zee heavnz” ;-) Such interaction is something I (personally) really like in presentations, even if they break a little due to this :-)

All in all, we managed to go through all of git’s basic features and in the end even mentioned rebase – which can be used to change the history of ones commits (there’s also the very useful git commit –amend), detached-HEADs and git-svn, which I didn’t use before as I feared a little to make a mess in the company svn-repo (and in all “my” projects I’m using git, so I never felt the need to use git-svn). Some guys sucessfully used it and really recommended it, thus… here I am, doing git svn dcommits on an daily basis… :-) I’m glad to have also learned something from this presentation, not just “showed what I had to show” :-) Now just a few links to very good resources about git:

• A Successful Git Branching Model
• Very good video tutorial on git
• https://git.wiki.kernel.org/index.php/GitFaq
• http://git-plumbing-preso.heroku.com – internals
• https://github.com/ – free opensource project hosting
• and of course: http://git-scm.com/documentation

After the presentation I made an small sms-contest where you could win an PJUG tshirt for guessing what github’s mascot is called like. I hope it was an nice positive accent to finish the session. Next up was the pizza and then 2 more Łukasz’s… :-)

• //TODO: watch on parleys.com
• download slides
• download video

Łukasz Żmudziński – “Project Lombok – Cause We Hate Boilerplate!”

Lombok, if you didn’t see it before is this -> http://projectlombok.org/ It’s a “total hack”, as the author describes it (and he’s right ;-)) but it allows some funny compile time hacks while writing Plain Old Java Code. Łukasz showed us around all the annotations which Lombok provides and how they work, what code exactly would be generated by them etc. The most “let’s you write less code” annotation would be @Data, which at compile time would cause Lombok (…here comes the important part:) to write the source for all setters, getters and toString hashcodes etc – so javac in the end, thinks it’s just compiling plain odl java… Here’s a link on how it works: Data.html The funny part about it is that it’s an compile time tool – much similar to Spring Roo in that aspect if you ask me -  and what it actually modifies is the AST (AbstractSourceTree) that javac then uses to generate it’s bytecode… So no bytecode magic – just how I’d call it… source code injection during compile time? Yeah, weird stuff.

And if you ask me not really something I’d be using all over the place. Sure it’d spare me the writing of some getters and setters and some more tricks but in the end, it’s a problem for not supported IDEs. (How do you explain IDEA that this class really *will have* an setBla() method…?) While NetBeans and Eclipse do have plugins to enable them to unserstand lomboks annotations. It’s not really enough – what about static code analisis tools? They’d go nuts with code that calls methods which dont exist in the source etc :-) Nevertheless if was a fun topic and it definitely is an quite funny javac hack, but if I’d be desperate for such features… I’d go polyglot coding with groovy or scala etc… :-)

• //TODO: watch on parleys.com
• download slides
• download video

Łukasz Czerpak – “Testy jednostkowe i integracyjne w przykładach”

By now you probably noticed it… There where almost only Łukasz’s presenting on this Camp…! :-) Łukasz Czerpak’s topic was about, generally speaking, TDD. He focused (as the title suggests, if you can read polish ;-)) on unit and integration tests. The border between them is sometimes a little blury, but the definitions he have were nice and clear – 1 class = unit, long setup involved = integration. It’s as easy as that, yet sometimes during discussions with other coders these sometimes get confised. Next he went on to some examples of how TDD is useful and finally to a lot of code examples. As he’s using EJBs at his day job, this part was mostly covered – and very interesting (for me, who’d usually just use spring and be done with it).

The mocking framework he used in his examples was of course our Polish Mockito… :-) It’s really great and lot’s of fun to work with, unlike some other mocking frameworks out there. Although easymock would take the 2nd place if I’d were to make an ranking. I’ve also seen a little JMock but it doesn’t “feel good” – but if youre interested in pure “what X can do”, they all do offer the same things, so why bother with some cluttery syntax? :-)

Next, Łukasz showcased using glassfish as an embeded container which definitely is on my “good to know” list and then continued on to an very awesome JBoss library: Arquillian [arquillian homepage] (see? It’s so cool I even had to mark it bold ;-)) It’s an lib which enables you to deploy (yes, “deploy” – perfect word choice) EJBs or even whole archives to an testing enviroment – which would then be started using an embeded container, although as seen on their homepage, they also support remote containers… interesting! Here’s another nice usecase of it: http://ocpsoft.com/seam/cdi-powered-unit-testing-using-arquillian/ The presentation was really well prepared and most probably the high

• //TODO: watch on parleys.com
• //TODO: download slides
• download video

That’s all folks!

We’ll be doing another JavaCamp in the near future (January perhaps…?). But for theese few weeks now we’ll be focusing on the upcomming GeeCON 2011 (Cracow) and kickstarting it’s call for papers (yay, I’m it’s author ;p). And if you’re interested in seeing all recordings on parleys.com and not just as videos – stay on your toes, because after Devoxx we’ll upload them there – I’ll update my blog then and we’ll write an quick news about it on java.pl In the mean time, you can go take a look at these and the previous (javacamp #4) recordings on camp.java.pl – which I just quickly set up to allow you guys quick access to the movies…

Yup, that’s all I think… see you on GeeCON || JavaCamp #6! :-)

As this years WARSJawa looked very interesting since it’s been annouced. I immediatly decided to go there – and tried to convince some friends to go with me. In the end, 2 friends came with me: Andrzej Grzesik (from PolishJUG) and Temporal – a LISP/Erlang hacker from my university ;-) We had to ride out at 5:00 to on time (driving so soon in the night really sux), but it was definitely worth it! Now let’s go on with a quick review as always after any conference:

Wojciech Erbetowski z PlayFramework

Wojtek started out the conference with an quick prezi.com presentation but then dived deep into the code and showed us an basic demo of the Play framework in action… I’m not really getting “turned on” by “yet another framework” so I wasn’t all too enthusiastic about it. Some things are really horrible in Play – all views are generated by static methods for example – oh God… Please dont force me to test such an application – you know, with multiple threads… ;-)

All in all: “I won’t be using this one.”

Dariusz [LocK] Łuksza z EGit i przyjaciele

As Darek has taken part in this years Google Summer of Code in the EGit project, he’s the perfect person to give a speech about this plugin. Sadly we encountered an bug in EGit during his presentation and it “broke his flow” a little – which I fully understand. Doing live coding/demos is really hard and I’ve seen a lot of experienced developers/presenters having problems with ther demos. It’s the so called “Weird, this did work last night!” or “Demo-” syndrome… Nothing you can do about it. As LocK’s presentation was mostly about clicking, I wasn’t so happy with it as I’m more of an terminal hero, and like to do all my git commands from the command line. Nevertheless, the EGit plugin seems to have improved quite a lot!

Btw the way… My friends from the PolishJUG have asked me to present about Git during the next JavaCamp (#5), but my presentation (while also being an live demo (oh please don’t allow it to fail… ;-))) will be purely terminal and git command focused. I hope you’ll like that approach…

Paweł Lipiński z “niespodzianką” – w ostatniej chwili za Sławka Sobótkę

This talk was one of the “fun” ones. No hardcore coding action, but lots and lots of fun and comparing everything to Agile. And Software Craftsmanship to a boy that won’t clean up his room etc etc. A very fun talk, but there’s not too much to comment on here, so let’s move on to the meat of this conference:

Marcin Rzewucki z Clojure – podstawowo i praktycznie

“This is the meat.” This is the one presentation that convinced Jacek (Temporal) to go with us to this conference. And I really have to say, it’s also what really tickled my hacker sense looking at the agenda. So, were we let down with just some basic intro..? NO, absolutely no. This presentation was very invofmative, easy to grasp and it turned out to be two presentations in one! The first part by Marcin was an intro to the language and how it functions, along with calling Plain Old Java from it. (Btw, kudos to Marcin for speaking so clearly even though he had some health (throat) problems  at that time)

The second part, which was taken over by Jan Rychter was entirely focused on the practical aspect of coding in Clojure in an commertial application. It was VERY, VERY interesting to see how and why one would use an functional (“very functional”, not just Scala) language to implement some application.

And don’t forget to add Marcin’s blog – http://www.clojureblog.pl/ to your RSS feeds!
Yet another link for starters: http://clojure.org/

Adam Michalik z Co w bajtkodzie piszczy?

You may remember my blog post where I’ve been decompiling string concatenations inside an for loop just to see how much more dump it produces. Adam’s presentation was just about that, decompiling and analyzing the ByteCode. It’s an very fun topic to look into and may lead someone into implementing some language on top of the JVM… :-)

But Adam didn’t stop at just analyzing the ByteCode, in the end he actually coded some fun stuff that the ByteCode allows us to do but the javac compiler doesnt – such as multimethods and calling methods of an interface (invokeinterface) on an Object object… ;-) There were some fun tricks included in his presentation and he seemed really compenent about this matter. “Bit fat 10 points for the man over here ;-)”

Rafał Rusin z Tworzenie zadań przy użyciu komponentów Open Source (Apache HISE, Apache Camel)

While being a little accustomed to (“I know what it is”) with Apache Camel, and seeing some sense in it. I really can’t seem to find any particuilar use case for my for Apache HISE. It’s an WS-Human-Task Spec implementation and aims to… wel… And that’s the problem I had during this presentation, I didn’t quite grasp why I would use it. The general concept of Human Tasks is quite easy to understand, but why I’d need Hise for it is not… One of the reasons I didn’t grasp it may be that we were dead tired after riding +4hours to Warsaw. Having that said, you may want to take a look at their homesite.

Summary

We all really enjoyed everything there in Warsaw, the great people (hooray for networking), food and last but not least the great presentations. During the few presentations we didn’t enjoy we were hacking some of emacs sources (using emacs of course… ;-)), and what a suprise – they’re mostly LISPs (the plugins). That was also a very interesting thing I took from this conference… I’d recommend you go to the next edition ot WarsJawa if you still haven’t been there… It’s even worth +8hours in a car on one day! :-)

Photos and more reviews can be found here:

• http://picasaweb.google.com/bartek.zdanowski/Warsjawa2010#5531326004503230818
• http://blog.japila.pl/2010/10/warsjawa-2010-za-nami-o-javarsovii-2011.html
• http://picasaweb.google.pl/Anna.Mazinska/Warsjawa?authkey=Gv1sRgCNm7mvryj7LcsQE#

PS: Yeah sorry for less links to projects and homepages than I usually include, but I’m kinda very busy right now… :-)

Łukasz Kuczera – Scala the next Java?

Łukasz’s presentation really did fit the topic and did a really good job in setting the “mood and feel” for the rest of the day. People who didn’t know any scala before – now did know it enough to understand all the code Jonas displayed later, and people who’ve known some scala before – might have got some nice information from this. I really liked it and am now more tha ever convinced of scala’s “perfect fit” nature in the JVM lanugages team. As I was sitting with my friend Temporal – who’s a real Erlang and Lisp hacker ;-) - I’ve got some interesting insights about what scala took from Lisp and later on, what Akka took from Lisp and Erlang. A very good presentation in my opinion. :-)

Jonas Bonér (private site) – Akka: Simpler Scalability, Fault-Tolerance, Concurrency & Remoting through Actors

A very very awesome speech and topic. Akka seems to do Actors and Parallelism very well. Also, thanks to my lisp/erlang friend, I’ve had some amazing insights about where Jonas got some of the implementation ideas. Also, we’d both like to note that some things are done even cleaner in Akka than in Erlang: in erlang you’d pass an actors PID around in order to “link” with another, and the links are always bidirectional. The actor pattern really powerful and scalable from what I’ve seen. It’s also implemented by Vaclav Pech in his GPars library (“Groovy Parallelism”).

This should have been just another presentation in a series of them as Jonas already had presented it on both Scala Days 2010 and GeeCON2010. But! As the present programmers really where into this topic we’ve had a lot of pauses with some chit-chat. A very valuable thing for both akka and our community :-) Too bad that Jonas didn’t have the time to go more into STM, as I still dont really know what it essetialy is “in practice”. Later we got a glimpse of Agents and what they could be useful for. All in all… go checkout the movie – it’s worth your time if you don’t know about parallelism and akka (I guarantee it ;-)): jc4-1-scala-min.mp4

Jonas covered and built upon the previous presentation, and we got to see some more scala in action – feels really natural. The transition from Java->Scala seems to be as painless as the transition from Java->Groovy. That’s a really nice thing I guess. There’s also an Java API for most the things in AKKA – so if you don’t want to adopt Scala in your project – no problems here. If you’d like to read more about AKKA, just goto their website at: http://akkasource.org/ – and yes, it’s open source. :-)

Oh, and if you’d like to see the slides Jonas used: they’re online on his slideshare: http://www.slideshare.net/jboner/akka-scala-days-2010
Also feel free to read this very in-depth post on his blog: Introducing Akka – Simpler Scalability, Fault-Tolerance, Concurrency & Remoting through Actors

Pizza

In the break we had some chats about the usual stuff – programming, companies, and of course a little something about the gaming industry ;-) The pizza was quite tasty – as always – so let’s move on to the next presentation ;-)

Bartosz Kowalewski – Is OSGi ready for enterprise use?

Yet another go with “grasping wtf OSGi is and WTF would I use it?!”. This topic was kinda new to Temporal, as he’s not into JEE Java, where OSGi now seems to be “trendy”. So after a short intro into maven/dependency stuff from me we focused on Bartosz’s presentation. I was immensly happy to see that his thoughts and presentation focused on “what OSGi should solve, and why it sometimes does NOT”. His code examples really cleared up what the problem is, and displayed why OSGi is sometimes a much harder to force to work properly than we’d think it should.

All in all, he described it as an amazing technology to play with, but if one would to use it IRL, with real deadlines etc – one should better know what he’s getting into, as OSGi does solve some things, but in exchange it introduces a lot of more compicated problems. The presentation was really good – as it focused, and really showed how/why OSGi should be awesome, and why sometimes it’s not – most of the time with needless complexity (!).

UPDATE: If your interested in the examples Bartosz has shown during his presentation – download this this zip file that he has made available. It includes the presentation, as well as the sources he used (plus the maven artifacts needed to run the app). Don’t worry if some tests fail – they’re designed to… :-)

Łukasz Kuczera – Lift – simply functional web framework

The last presentation was again Łukasz, continuing in the spirit of this “Scala-flavoured-JavaCamp”, with Lift, an web framework with quite some nice contepts – as view first etc. As it was more of a code-trip, showing the basics of lift, there’s not much to comment on here.

I was kind of disappointed with Lift. It really didn’t seem to be as powerful or mature as Grails of Symfony for example. The “view first” pattern is of course nice and quite well “forced”, but it didn’t strike me to be any different than just Django templates. The CRUD also does not impress someone who’s been using Rail-ish stuff for quite some time. There was not much said about the ORM, but I feel quite comfortable with GORM and the routing system is waaaay overgrown – just look at symfony/grails/rails routing files – they’re short and easy – what I’ve seen in Lift does not seem to be short – it’s quite long and with lots of empty [] etc… I may come back and take a look at lift when I have the time, but it really didn’t impress.

Videos and sources from the meeting

The 4th edition for our JavaCamp was truly amazing in my opinion, and this time, we’ve even got an amazing place, sponsors and great speakers. Have a nice holiday all! And if you didn’t manage to be there live, you can always go to the page bellow and watch the video’s I’ve recorded from the meeting :-)

All videos are temporarily available on my server – here: http://pjug.project13.pl/
I’m hoping to get them up on the java.pl server soon, or better, on parleys.com – but we’ll see about that. :-)

PS: The next camp, won’t be organized so soon – but from what we’ve planed, we’ll be goring into some groovy topics most probably… But don’t take my word for it ;-)

So the long awaited GeeCON 2010 has come to an end yesterday. Of course I was there, and had quite an amazing time there yet again. Here’s, as usually, a small review/roundup of al the three days GeeCON lasted. It’s been really fun, as I was not only attending all the sessions but hanging around with some of the speakers – that was the most fun and interesting part I think.

Day 0 – VeryBerry

After an long 8hour trip by train, we (I was with two friends this time) finally arrived in Poznań. We stayed at the VeryBerry hostel and I’d really like to recomend it to anyone who’d like to stay in Poznań, the prices are low but the service is top notch and the rooms really new and neat :-) After some minor coding, we went to sleep and got read for…

Day 1 – GeeCON University: Gradle Training & JUGs @ Poznań

Gradle Training with Hans Dockter

I was quite interested in Gradle since I’ve seen it in action at SFI (JavaCamp #3 had the same presentation) so I was really happy to be “trained” on it by Gradle inc CEO – Hans Dockter. Apparently they are using it a little (main stuff is still in maven) at SoftwareMind. The training sadly didn’t include as much coding as I’d wish it would, but as Hans said, there’s too much of us (it was the most popular training) and we had 1 day instead of 2 which usually this training would last. The topics where well distrubuted and now all trainees have a really good basic knowlage to start out with gradle. I’m hoping to do this in my soon projects, some ant task usage from within Gradle will be required to build GWT/Vaadin stuff, but hey – the integration is really awesome.

Another fun part was getting home from the University (it’s really awesome by the way) as we took one cab with Hans Dockter and Oliver Gierke (who talked about his Hades project on the 2nd day). We chatted a little in German and dropped them of at their Hotel. Next stop… JUGs meeting~!

JUGs @ Poznań (more info)

This was an short (2h) meeting of the PolishJUG and PoznańJUG. Here we met the rest of my PolishJUG pals, such as Marcin Gadamer and Miroslav Kopecky. And also Geertjan from NetBeans as he was presenting NBPlatform to the JUGs. It was a quite fun session as there was both Chris Aniszyk from Eclipse (and also an OSGi expert) and Geertjan Wielenga with NetBeans Platform – both of which are nice platforms to develop on. The final talk was by Ed Burns in which he presented how the UI enviroment was evolving during the last years and how desktop vs web is now batteling for the users attention. All three would eventually present their talks at the first day of GeeCON – Geertjan dropped in as Ikai Lan replacement as he got really sick and couldn’t do his speech (in case you’re wondering why he’s not listed in the speakers section).

Later we went to a nice Pub called Fuego where we had some interesting conversations with all the speakers and members the Polish and Poznań JUGs… Let’s move on to day 1, shall we..?

Day 2 – GeeCON & Geeky Pool Party

Thorbiörn Fritzon
The Future of Java

The first (and also sponsored ;-)) presentation was done really professional and was mostly about assuring all present programmers that oracle does care about the java community and will continue (even more than sun) to evolve java. Well, this might me be true, but the presentation, while really amazing from the visual side, didn’t really involve more facts than the statement about Java Oracle has released a while ago.

Holly Cummins
Apache Aries: Enterprise OSGi in Action

I hoped to really grasp the whole OSGi concept after this presentation and partially I did. Holly did kind of introduce OSGi to us and tried to show it in action – which sadly didn’t go to well (loosing the war you need to deploy can be quite an problem… ;-)). One thing that Oliver didn’t agree on is that she said that Class loading is the best thing about OSGi, yet as Oliver and some others tweeted – it’s just an enabeler for Services to exist.

Craig L Russell
Easy to Use Highly Available Java Database Access

This was a presentation about the MySQL’s Cluster storage engine. It was interesting to see how such technologies are in fact used from the code – it’s quite easy actually – almost like using an normal MySQL instance. There are some limitations of course – as the lack of relations etc. but if you’d need HA and Fault Tolerance it’s definitely one way you could go.

Some of the talk was about ClusterJ which is an slightly more advanced way to interact with your Cluster from Java… More about it can be read here

Christian Tzolov
Rapid Server Side Java Development Using Spring Roo

Though I didn’t attend this one, I included it in this review in order to say this: Roo ownz (any command line tool that really helps at dev time ownz) :-) I’ve seen some of it in action some time ago, and it’s really helping while developing what you’d call “plain java apps”, without the goodness of Grails generate stuff… If you still haven’t seen it in action: take a look, its definitely worth it. (It’s an development time only tool that like the grails command line app, can really speed up your development time with setting up basic Domain Objects, Persistence etc…)

Eugene Ciurana
The High Availability Non-Stop, Fault-Tolerant Services Tutorial

A very good talk about scalability and availability. Eugene explained to us what the typical bottlenecks could be and how we can cope with them, by scaling up or out – (at last someone clearly defined those two to me). Some of his real live examples where really interesting as one company that switched to an cluster to store their data and not OracleDB what would cost them A LOT… All in all, it was quite educational but sadly – it’s something I won’t be seeing in my upcoming years as “novice developer”.

Ed Burns
JSF 2.0, Myth and Reality

As Ed is one of co-spec lead for the JSF 2.0 (and also “worked on a wide variety of client and server side web technologies since 1994, including NCSA Mosaic, Mozilla, the Sun Java Plugin, Jakarta Tomcat and, most recently JavaServer Faces.”) we were all really interested in his talk. He addmited what they did wrong with JSF 1.x and showed how most of the problems where adressed in the 2.0 release. Is was a quite nice talk, but sadly (and with some maven problems ;-))

Matthias Wessendorf
Practical Comet and JSF

I’ve been really interested in ServerSidePush for a long time, so this was an really fun presentation to watch. There were some implementations and Java Libraries shown. If interested, take a look at Atmosphere on java.net or the Dojo implementation which I’ve been reading about lately. (another nice link) All in all, it’s not quite there yet, and will sometimes have to fall back to polling. Hopefully websockets from HTML5 could be a nice thing to use comet in all the future browsers.

Vaclav Pech
Get ‘em before they get you

Geertjan introduced me to Vaclav Pech sometime during GeeCON and also I’ve been following him on twiiter quite for a while, and I must say the stuff he coded is really impressive – and all his presentations were well prepared and fun :-) That said, let’s move on to this particular session.

A sponsored talk, but nonetheless quite interesting, as Vaclav showed us how to even better utilize all the features that IntelliJ IDEA has. Most of the tools where known to me, but some where new or interesting (it’s quite simple to write your own inspections btw!) The parallel session was Ed Burns with his “Rockstar Programmer” book-talk, Vaclav noticed that Ed’s talk probably has the people who need to become such programmers, while this one has people who already are… ;-) Following that idea, Vaclav went bughunting with us and all the various IDEA tools – it was a nice presentation, with a good link between the audience and him :-)

Geeky Pool Party

In the evening all Geeks where invited to the Black Pool (Pool Club) where one had an occasion to talk with fellow developers and speakers. We had a nice talk with James Williams – not only (but mostly ;-)) about development but also how education works in Poland etc etc… Later I joined the GeeCON and Sun teams at the Pool and played a little with Łukasz (not sure of the name, sorry!?) who recognized me as the “guy from JavaCamps with Shadowman on the laptop” :-) //That said, Shadowman FTW! :-)

Day 3 – GeeCON & GeekTrain back to Cracow

Oliver Gierke
Easing JPA DAO development with Hades

Hades is an really nice way to speed up your DAO development, read more about it here: Synyx Hades. I’ve bee riding a cab with Oliver before and already heard how good of a programmer he seems to be, the presentation just confirmed this. Hades is really well thought out and intuitive to use. Most of the time, all you have to do is write an DAO Interface, that you then use to access your data… Yeah, just an interface – no implementation needed – all the implementing is done by hades. It looks at the interface and tries to guess what an method should be doing, most common prefixes as findBySomething or findAll or other get’s are supported and generic. When you need an custom implementation, you can easily do this as well, and it’s possible to reuse named queries… Really nice, and the upcomming version will be JPA2.0 compatible :-) Big kudos to the Hades team…

The sources used in the presentation can be found on github: http://github.com/olivergierke/hades-geecon

Vaclav Pech
Unleash your processor(s)

A really nice intro into paralelisation – NOT multi threading. Vaclav presented such abstractions as Actors, Agents, Fork/Join and Dataflows… Of course most of this was shown in Groovy as Vaclav is involved in the development of GPars. It’s been quite insightful and now I also know what this AKKA thing is that some people are so fascinated about. Also some Scala and Cloujure examples where really fun to investigate – scala in fact is in many ways so very much elegant and ideal for such sollutions – though Groovy GPars also has me convinced. The withPool 4 {…} is a nice feat for example, and thats just the tip of the iceberg.

Joonas Lehtinen
Vaadin – Rich Web Applications in Server-side Java without Plug-ins or JavaScript

I’ve been trying out vaadin lately and it’s quite nice. Above all, it’s “a GWT that looks good”. The presentation was lead quite profesionally but all in all didn’t really show any “meat” od the framework. One thing I’m concerned about is the (as Hans Dockter likes to call it) “Frameworkitis“, I’m kind of afraid that it might be hard to force Vaadin to do things that the projectant’s didn’t think about… I’m hoping to continue to code my simple rss reader with an vaadin front end – and also I’d like to add some simple JAX-RS powered REST access to it…

James Williams
Game Programming with Groovy

We’ve had a nice talk with James during day1′s pool party. He’s been using Grails lately and is working in the US. His talk was ment to be a more fun/geeky one, and showed simple groovy apps/games, one involving JavaLibrary usage to access the Wiimote sensors. Thus, the code was mostly “looking like java” and not much groovyish was in there.

Charles Nutter
Duby: a Fast, Ruby-like Language for the JVM

I just the last part of this talk, as James didn’t take all the time he had so I went over to look at “this Duby thing”. The best quote I’ve head from GeeCON comes from this talk, it went something like this:

Obviously I’ve been looking at the JVMs source a whole lot. [...] So what’s the neatest feature we all would like in Java…? MultiLineStrings, for christ’s sake!!! [...] And I’ve been looking thought the Java’s sources and there is one single damn if statement, that basically says: “If string, dont allow multiple lines”. And I was like “… You ****!!! For all those years…!! Argh!!!”

Vaclav Pech
Groovy actors and concurrent dataflow with GPars

It was basically the same (well, with more code examples) presentation as the one I’ve seen before, so I switched and went to see Adam Warski and the Checkers Framework.

I also had a small talk after this with Łukasz who recognized me from the JavaCamps and has been presenting on the 1st JC on his Swing/JNLP usage at his work. Sadly I wasn’t into Griffon since then so I couldn’t really give him more tips about it more than that it looks really promising from looking at the examples.

Adam Warski
Static analysis using JSR308 annotations

The checkers framework is a new thing to Java and it basically allows to annotate Types, in a current point in time. Your method can require an @Hashed String and would not compile if passing it an normal String it opens up quite some interesting interactions, some of which Adam has implemented in his TypeState checker which is checking the status of collections if it is safe to read from some place in the code or not – by setting the collections @annotation to certain States (like “you haven’t called isReady, do please dont read from me!”). It’s an interesting way to detect errors in your code before execution time.

Bruno Bossola
Object Oriented for nonbelievers

One of the most fun talks on GeeCON. It was about how we somehow strayed away from what OO used to be, ObjectOriented Design. Nowadays people start out not by building an ObjectModel of their Domain but look for frameworks to use… His talk was there to bring us back to the basics what OO should be about and showed some patterns in use (simple, yet effective). One particulary fun quote from this talk is the last sentence:

Why am I calling this talk “for nonbelievers”? Well… You all agree with me that OODesign is important, but tommorrow you’ll go back to choosing from all those fun frameworks anyways! ;-)

Mark Struberg
JSR-299 Context and Dependency Injection

An very important topic as DI gonna be standarized now… Sadly Mark’s voice was quite monotone and we were all powered out at the time… The presentation as such, was very well prepared and later there was some source shown – that’s how I like it.

End of GeeCON 2010

After some “bye bye” with crew members and speakers, we went to our hostel and back to Cracow – it was a fun event, hope to come back next year. What would I like to be different? Well, more awesome speakers – Scott Davis would be really cool, I’ve seen his talks on JDD09 and they really changed how I think and code. He opened my mind to “Java the Platform” and Groovy and all the other awesome languages. Such speakers would be more than welcome anytime! Oh, and more “hands on”!

GeekTrain back to Cracow, and an surprise meeting :-)

In the train we met some fellow programmer who recognized our GeeCON stuff and most of the trip we where talking about the conference and our studies/work… It was a fun ending for a fun conference… ;-) See you next year!

Amazing days and awesome people

It’s been some amazing days for me during (and before) the NBPTraining. As you probably know already – I’ve been the “one-man-army” behind the organization and basically everything around this training. I got lots of help from various people, such as Dr Jarosław Wąs (from KN Glider) – it wouldn’t have been possible to make this training such an success without his great and very active support. And of course – the PolishJUG, which I’m a proud member of! :-) But one thing I have to admit, Bureaucracy is a horrible thing and really made some things (needlessly…) difficult – thank goodness in the end, we had everything well organized – as Geertjan put it on dZone:

[...] There are also some illustrative pics to share, to give an impression of the group (really large), the trainers (really busy), and the organization (really good) [...]

Day 0: Welcome Dinner

What’s so worth mentioning about the guys just coming here anyway? Well it was a quite trip for some, especially Geertian, who had to come by train which took him about 27hours instead of just coming by car from Prague. All because of Eyjafjoell‘s eruption last week… And Toni and Geertjan were in Oslo at that time, doing a Training for an company (btw nice interview with Gunnar Reinseth) – so we were worried if they’ll be able to come to Poland due to all the flights being cancelled… Anton was lucky and but Geertjan’s original flight got cancelled… Well, he had quite an interesting journey as he called it himself :-) Later when Karol joined us and soon we all went to eat some pierogi and chat a little :-)

Days 1 & 2: The Training

Thanks to dr Wąs everything went smooth and without any problems… Even though some other students also wanted to use the room we had reserved – due to the chaos caused by the tragic plane accident and them wanting to make up for the classes they’ve lost last weekend due to the burial ceremonies… I’m really glad we managed to get the training rolling with absolutely no problems – we were really prepared for everything, along with backup projectors etc ;-)

If you’re not very familiar with the Java World – please note, that the training was NOT about NetBeans IDE. Yeah, we did use NetBeans IDE (there’s some nice little helpers/wizards), but that’s absolutely not a must – NBP is pure Java (just a bunch of jar’s) and XML – so you can use anything you want to code stuff based on NetBeans RCP. That said, the training was about real coding stuff such as patters used in the RCP, use-cases and “ how do I code such a feature  to scale well?”.

The agenda was the basic NetBeans Platform Training as outlined on http://edu.netbeans.org/courses/nbplatform-certified-training/ that’s a good thing, as only a few students actually have used the NetBeans RCP (or even ANY RCP) in their lives. The level of participants was quite diverse, some saw loose coupling in action for the first time in their lives, and others were already planing some advanced use-cases foe the things we were learning. The sources and videos for most of the examples are also hosted on netbeans.edu.pl, so if you want to know what you’ve missed, feel free to download/watch them (if interested in FullHD versions, contact me per email). The Lookup and Nodes/Explorer Views were the most interesting features of the platform I guess. Of course having an full blown app with menus etc out of the box is also nice, but not a “life changer” if it weren’t for those mechanisms. Sadly we didn’t talk about the Lexer API (for parsing languages) but I personally talked with the guys a little about it – and why schielmann was dropped etc… A really fun and interesting insider talk :-) I simply love such conversations…

After the training Geertjan gave away a copy of his book (“Rich Client Programming”), to the person who asked the best, most interesting questions during the course. Of course it was then signed by all the trainers. Sadly I don’t have a picture of the books’ winner, nonetheless – congratulations! After the training I also asked the guys to sign my copy of the book, hurray for signature collectors ;-)

Anyone interested in some of the response I got concerning the training? After the training plenty of you mailed me and thanked via forums etc, here’s a few responses:

przyznaje, na prawde baaaardzo fajne szkolenie

Faktycznie – świetna robota. Wielkie dzięki ;)

Tru. Gj.

[...] nie udalo mi sie zjawic a slyszalem ze bylo super ;/

[...] bedzie problemem jesli przyjde jutro na to szkolenie NetBeans’a? Bo slyszalam ze duzo ciekawych i przydatnych dla mnie rzeczy jest wiec chcialabym sobie posluchac :)

See you next time!

I hope you all enjoined the training – we certainly did. I’ve got some opinions from happy participants, so I guess everyone liked it as much as those did.

If you have anything (opinions, sources or even complaints) feel free to contact me: kmalawski@project13.pl or just leave a comment here :-) Also, when you get your NetBeans Certified Engineer and would like some more promotion for your open source project – let me know and we’ll add a link to it at netbeans.edu.pl!

Some students have already  have started their projects based on the NetBeans Platform – so what are you waiting for?! ;-)

What’s next for me?

Well, I’m going to GeeCON, to learn about Gradle, and tap into facts and myths about JSF and other things (the list of good topics is really long so I wont list them all here, just have a look on your own). The agenda mostly caught up my attecion and I’m really happy to be going there. What’s new for me + conferences is that I don’t have to go alone anymore. I’m going with a friend (some years older) and potentialy another girl – as she won the Google trip to GeeCON… ;-) I’m also really happy to be able to meet Adam Dudczak, thanks to whom the whole NBPT idea got ignited in me and the NetBeans Guys :-) Of course we’ll meet up  with all the PolishJUG members, (Adrian Nowak, Radosław Holewa, Marcin Gadamer and Kuba Dżon) and Miroslav will be comming too – lot’s and lot’s of programming-friends :-) Seems like Toni and Geertjan will also be comming, yay! Yeah, so that’ll be 3 days in May… but that’s not the end of my Java related stuff in May:

Later in May I’ll be on an Spring Source Training. It’s only the “short introductory one”, and I’m well aware that it won’t make me an spring-guru, but an insider insight about Spring, Roo or Grails is also a good thing to have.

By the way, did you notice that the netbeans.edu.pl is running on Grails? I’ll release it’s sources when they’re polished enough~! Viva la free software.

Geertjan, Toni, Konrad (me), Karol

Oh, and for those asking: Sadly I didn’t own an PolishJUG T-Shirt at the time of the training, so I took the most Java related I had – from Java Developers Day. Also a quite nice conference… :-)

Niestety tego samego dnia, około godziny 9:00 doszło do katastrofy polskiego samolutu z b. ważnymi osobami rządowymi i nie tylko Polski… Trudno jest sprawę opisać słowami i chyba każdy wie o czym mowa, także podobnie jak na JavaCampie, pozostawiam to w chwili ciszy i kontynuuję z materiałem…

[...]

Piotr Jagielski – “Testowanie z użyciem obiektów zastępczych”

Świetna prezentacja na której w końcu zobaczyłem EasyMock (okazało się że wcale nie jest taki Easy jakby nazwa sugerowała) Mockito oraz PowerMock w akcji. Jedyne co miałem dotychczas wspólnego z testowaniem przy wykorzystaniu Mock obiektów to ręcznie napisana MockCrosswordGenerator – okazało się że jest to w pełni normalne i porządane czasami podejście do mockowania – także ucieszyłem się że moja domorosła odpowiedź na pytanie “jak to sensownie przetestować + słyszałem coś o mockowaniu ale franeworka to mu tutaj nie trzeba” pod tytułem “a napiszę klasę co implementuje ten interfejs i zwraca gotowce” okazała się być normalnym i słusznym w niektórych sytuacjach podejściem.

Wracając do przedstawianych bibliotek -  Mockito wydaje się faktycznie przyjemny (no i był mocno reklamowanego podczas prezentacji), chyba że znajdę coś lepszego… Groovy wydaje się trochę fajniejszy do takich rzeczy “na szybko”, no ale może już dość pakowania go wszędzie gdzie się da hm hm… Mockito po przedstawionych możliwościach i przyjemności pisania testów w oparciu o niego, jest bardzo przyjemny.

Potem Piotr pokazał jeszcze armatę jaką jest PowerMock… Która po prostu potarfi mockować wszystko – magicznie. Bo jak wiemy niezbyt da się mockowanie zastosować przy metodach statycznych czy metodach/klasach finalnych. PowerMock trochę “czaruje” bytecode’em i nawet takie trudne sytuacje potrafi mockować… Co fajne – buduje on “na” tym co już mockito i easymock zdążyły stworzyć – nie jest to kolejne API które trzeba kuć absolutnie od zera :-)

Prezentacja była na prawdę świetna i chętnie posłuchałbym Piotra ponownie na jakimś innym spotkaniu.

Tomasz Kaczanowski – “Gradle”

Tą prezentację Tomek przedstawiał na tegorocznym Studenckim Festiwalu Informatycznym i akurat na niej miałem okazję być (oraz na prezentacji Jacka Laskowskiego oraz “warsztatach” z GWT… ale o tym post kiedy indziej). Także “nic nowego”, co nie zmienia faktu iż była zarówno wtedy jak i teraz porządnie przygotowana – co na prawdę było widać, oraz prowadzona “z sensem” – jakieś tezy, jakieś zestawienia, przykłady a następnie sprawdzenie co faktycznie Gradle nam daje a czego nie.

Na JavaCamp w przeciwieństwie do SFI było obecnych więcej prawdziwych programistów Java na codzień pracujących z Maven2, oraz będących dobrze poinformowanych o nowościach w Maven3. Dzięki temu prezentację często przerywano i dyskutowano na temat “czy gradle pozwala na XYZ” lub “w Maven też da się ABC” itp. Bardzo mi się to podobało, z dwóch powodów: prezentację już znałem więc powiew świeżości był mile widziany oraz “życiowe” spojrzenie na prezentowany materiał zawsze jest najważniejsze a na “wielkich konferencjach” często unika się takiego spojrzenia. Słowem? Kolejna bardzo dobra prezentacja z dużym zaangażowaniem publiczności.

Waldemar Kot – “Współbieżność w aplikacjach Java EE”

Bardzo bardzo podobną prezentację Waldemar prezentował Java Developers’ Day 2009, gdzie również miałem okazję go posłuchać. Tam prezentacja nazywała się “Asynchroniczność, współbieżność i rozproszone przetwarzanie w Java EE
- przykłady z użyciem technologii middleware Oracle: WebLogic Server,
EclipseLink/TopLink JPA i Coherence” i jak można zgadnąć po nazwie… było trochę “hmmm”. Tym razem, pod prostszą nazwą, i odświeżonym podejściem Waldemar skupił się na pokazaniu nam WorkManager API – de facto standardu w przetwarzaniu równoległym w JEE. Bardzo ganił dziwne podejście ludzi który twierdzą że współbieżności w JEE “się nie da” (pewnie że się da, ale po prostu nie Thread’em droga) lub “a jeśli musisz to użyj JMS” – dziwne podejścia, faktycznie – skoro WorkManager jest tak ładnym i banalnym API… Standaryzacji się niestety wątki w JEE nie doczekały, ale WM jest dobrym i sprawdzonyum rozwiązaniem. No i mamy również w springu: http://static.springsource.org/spring/docs/2.0.x/reference/scheduling.html Więc w sumie zaskoczył mnie że spotykał się z takimi poglądami dot współbieżności a JEE…

Potem mała prezentacja tego co taka współbieżność w efekcie daje – przykładowe odpalanie wątków i zabawa ograniczaniem ThreadPoola z poziomu serwera aplikacyjnego – to samo było na JDD jeśli dobrze pamiętam.

Kolejne demko dotyczyło już Oracle Coherence. Czyli witamy w świecie DataGrid. Jak to najprościej opisać? “Taka Map… rozproszona na 200 serwerów i samoczynnie replikująca się do baz danych z np. opóźnieniem – dramatycznie redukując ilość zapytań SQL.” Oczywiście to nie tylko tyle, ale również dostęp poprzez Java/C++/.NET do jednej i tej samej instancji serwera. Prezentacja była fajna i ciekawa – szkoda że takie cuda dopiero mają sens gdy ma się miliony zapytań dot. danych – ale technologia z pewnością jest bardzo ciekawa – a wydajność “widać”, skalowalność również ogromna… Cud miód i orzeszki. Na tym się coherence oczywiście nie kończy – pomysł wysyłania “kodu do wykonania” (uproszczona nazwa oczywiście…) zamiast pobierania danych, zmiany, i wysłania również jest fajnie wspierana. Zamiast na bazie danych i SQL po prostu pracujemy z API coherence, które pozwala nam tworzyć pewne zapytania – przedstawiony przykład był takim SELECT AVG(…) FROM, ale wykonanym na mapce coherence… Zwyczajne włączenie kolejnego serwera pozwalało drastycznie zmniejszać czas potrzebny na wykonanie takiej operacji – serwery same się dogadują i replikują między sobą dane aby potem wykonać 1 zapytanie (nic nie programujemy co by mówiło o jakiś serwerach) na wszystkich serwerkach na raz – ot takie podejście do współbieżności. Bardzo ciekawa technologia, no ale niestety wielka armata – chciałbym kiedyś z takich strzelać ;-)

Informacja dla zainteresowanych UniversityDay na GeeCONie:

Waldemar Kot będzie przeprowadzał na UniversityDay całodniowe szkolenie z Coherence – więc jeśli Cię to zainteresowało – zapraszamy.
Inna z ścieżej najprawdopodobniej będzie dotyczyć Gradle, także jeśli interesuje cię gradle, miej oko na informacje publikowane na stronie domowej GeeCON.

Pizza jak zawsze – dobra ;-)

Powyższy post napisano na nudnym wykładzie… ;-)

NetBeans.edu.pl

Since Poznań JUG’s NetBeans Platform Training in January (yeah, the one where there was no place left for me ;-)), I’ve been in contact with Poznań JUG‘s Adam Dudczak, Polish JUG‘s Adrian Nowak, Sun’s Geertjan Wielenga and Eppleton’s Anton Epple and many more… And a little later Karol Harezlak joined the training team. We’ve been planing to organize an NetBeans Platform Training in Cracow – since there was really an gigantic response to the training. Now it’s April… and just around two weeks to the NetBeans Platform Certified Training Kraków 2010 ;-) All this could not have been possible if not the great help and support from both JUGs and an amazing amount of help we got from Glider from my University. Also I’d like to give a big thanks to everyone I’ve met during this long process of organizing such an meeting – you’ve all been a great help! :-)

Allright, so what’s this NetBeans Platform all about? To put it simply, it’s “something” (a platform ;-)) that allows you to use all the stuff you see when you do your daily coding in the NetBeans IDE and code up your own application really quickly. While WebFrameworks are really popular and there’s a ton of them, there is not much (worth mentioning) “Desktop App Frameworks” as one might call them. Such apps are then called Rich Client Applications (just a fancy name for “Desktop Apps” ;-)), which makes NBP an Rich Client Platform… You may have heard about “Eclipse RCP” or “SWT” or “Spring RCP” – they’re in the same legue as NBP. But why is NetBeans RCP more interesting than the rest? Well here’s a cupple of reasons I personally find important:

• It’s all swing based, and as Java programmers – we know swing, not necesarrily some “SWT” or “Swing RPC” – right? Less totaly new stuff = better learning curve.
• Your app gets an windowing system abstraction, file system abstraction,  lots of GUI elements out of the box – Tree’s etc
• You can just extend NetBeans IDE or build your own app that looks like an IDE… or doesn’t look like one ;-)
• It’s 100% modular – that means you can use just the stuff you want, or can easily exchange or “lookup” (important word in the NetBeans world) stuff in order to develop apps that can handle plugins and are easily extendible.
• There are quite some inteligent and interesting opinions about NetBeans RCP vs Eclipse RCP on Adam Bien’s blog – (found this blogpost thanks to @timoreilly)

I find the Lexer Api quite interesting but didn’t have the time to really dive into it yet – basically it allows you to write programming language parsing, support into your app or netbeans IDE.
The most amazing… Hmm let’s say “the most visually amazing” app based on the NBP I’ve seen is Gephi (video below). There are lot’s of very complicated apps for biology or airlines and stuff) based on NBP, but let’s face it such apps don’t create an “WOW” effect, unless you totaly understand what’s going on inside of it.

Take a deep breath, and enjoy
NetBeans Platform + Gephi = Graph Awesomeness

Łukasz Lenart – “Google AppEngine – chmura na Ja(v)wie”

Łukasz, from the Warsaw JUG, was talking about Google’s AppEngine – it’s baisically Just Another Servlet Container but since it’s in a Cloud, it’s (potentially) easy to scale an application deployed on it… But the biggest benefit of deploying to the AppEngine is in my opinion: free java hosting. If our app doesn’t exceed some specyfic quotas (most importantly is smaller than 500MB – concerning the Data/Blob Stores) we don’t have to pay Google for the hosting. You could call this a free cloud for beginners, and if your app gets bigger, you’re kinda trapped in this clound, and then have to pay google some fees for the extra bandwidth etc.

Sadly not everything is “allowed” and we are restricted by a Java Class WhiteList. Also, there is no Relational Database available for us on the AppEngine – instead we can use the “DataStore” with GQL (or JDO or JPA) and for files there is the (now in “beta” status) BlobStore – the name explaing everything I guess… ;-) Another “restriction” would be not being able to access the filesystem. I can only guess why, but it would seem that this would make the AppEngine easier to scale… (sadly I’m not an AppEngine Developer so that’s just my wild guess). Ok, but why did I put the word “restriction” in quotes? Because I don’t think this “restriction” is that much of a hurdle… We can always use resources from inside our WAR by using Class.getResource() (I didn’t test this on the AE, but it sounds plausible and should work) and for uploaded files there’s the BlobStore. There are some more “services” like simplified threading (normal java threads wouldn’t be easy to controll by the AppEngine I guess, so that’s why they introducet this option) and some more – there’s XMPP, Mailing support etc…

All in all, I wasn’t a big fan of cloud’s to begin with, and even though the AppEngine seems like a nice place to Deploy, I’m not really convinced to go with it. The presentation was all right and I did learn some thing’s about the AE I didn’t know before – and the “show what doesn’t work and not what does work out of the box” apparoch Łukasz took, was really nice much more interesting than just “click… yay it’s working” – as it doesn’t go like that IRL most of the time…
That said, I’ll stick with a Tomcat server for my GWT-Crossword.

Oh, and the slides are available here and the source code of the demo (“Struts2 on AppEngine”) he showed can be pulled from mercurial by:

hg clone https://lukaszlenart-wjug.googlecode.com/hg/ gruuf-done

Miroslav Kopecky – “Outlook to Android Application Development” (yup, another Google product today)

I own an Android powered (and there for Linux powered :-)) HTC Hero since two days, but am not “new” in the Android API as I’ve been reading quite a bit about it since it was announced alongside with the G1 (or was it announced before the phone..? hmm…). Mirek’s presentation was an introduction into the Android Platform, or as we noticed “Framework”, as coding Android apps feel’s very much like using an framework (yes, every API is more or less something like a framework, but the “feel” here is really framework-ish, with lot’s of method overriding etc.). After some introduction into an Android Apps structure, Mirek went on and showed 4 application demos. They were using simple layouting, Contact access and at the end event Google Maps. It may have been hard to follow for people not accustomed to Android and wasn’t all too in depth, but the overall idea most probably came through.

I’ll write some Android App for sure in some time – first I’ll have to quickly finish my GWT-Crossword… It’ll probably be a ContactMerger – something that’s clearly missing in all google apps and is constantly nagging me. That is, an app to easily merge contact duplicates into one contact. This could be really nicely automated, and when some conflicts are detected a normal 3-diff-like dialog would be enough to quickly merge a few contacts into one… Sadly my HTC Hero still has the uber-old Android 1.5 and the contact’s access API has significantly changed since then… I think that by the time I’m ready to code for android  the 2.1 ROM Upgrade for my Phone should be available… So I’m focusing just on the “Level 7″ API (“level 7″ means “android 2.1″, whereas “level 3″ means “android 1.5″).

Piotr Maj – “Jak czerpać przyjemność z programowania w świecie krótkich terminów i parcia na słupki”

This presentation really stood outfrom the rest, it was fun and while not really tech focused, quite interesting. Piotr started out with some awesome [plastelina] figures that his wife made esspecially for this presentation: a “Garniturek” (Marketing Guy), an Programmer and an Evil Looking Tester. The figures were really hilarious… :-) Anyways, he started out with showing sources of [depresion] bad feelings in our day to day jobs, and pointing out that if we do something again and again, and still are doing it the same way – something’s not right, we don’t evolve if we code like that… Then he went on with introducing the Tester figure and some scenarios of a Tester humiliating Programmers. A few words about Selenium and then we were talking about how writing tests it both necessary and potentially really interesting. So in the end, we ended up talking about Unit/Functional Testing and Test Coverage – who would have thought, by the title of the presentation I was expecting something else, but it was a really plesant presentation nonetheless, and the need of testing code can’t be stressed enough I guess – maybe I’ll start to have a major test coverage of my code thanks this constant nagging about them ;-)

Pizza Time

During the pizza-break we had a long talk with Miroslav, and people could play around with the Nexus One he brought especially for this presentation. It’s interesting to hear out other developers views on some API. I for example find the Android API quite nice. The “J2ME Hell” I have been coding some stuff for burns even fiercer now that I have the option to choose another Mobile Java Platform – at last with cool things like SQLite, Widgets and Easy Touch Responsiveness – oh an the BackGroundTasking is a great feature – something J2ME never had I think, on the other hand, what good stuff did basic J2ME have? Yeah there were some JSRs that made life not so painful on ME, but on most of my phones there always were problems with them – MMAPI for example, where you sometimes had to code something SE or NOKIA specific – so where is that “write once” gone on ME eh…? Later on we talked with Miroslav and it seems that he’ll be at our SFI next month – yet another great conference… :-)

One of the developers had an Motorola DROID, which I have considered buying but decided for the HERO – for money reasons… The DROID’s (MILESTONE’s) phicical keyboard really sucks, by the way. That, plus the fact of how awesome the on-screen-keyboard of Android is made me not regret buying a phone without phisical keyboard… ;-)

Marcin Kalas – “Java/JEE Performance Test Planning – How To Plan Successful Performance Tuning of Java/JEE applications”

I had really high hopes for this presentation, as I’m currently doing JMeter Load Testing on MySQL engines at my University. Sadly this wasn’t a “practical” or “hands-on” presentation. Yeah, I understand that it’s really hard to show this kind of stuff in such a short period of time, nonetheless I hoped for some more “tricks and advices”. The some tips about the JVM and multiple GC Strategries were quite interesting, but that’s something I’ll need to lookup and read about when I’m going to need it as it’s clearly a very big topic.

Marcin surely has a lot of experience in performance tuning apps that’s clear and it was really interesting to see some people (Java Gurus) from the audience throw some interesting stuff into the presentation. Real JEE apps are really something amazing, I hope I’ll be able to code and work with such apps in my future, it’s an amazing world full of Gigantic DataCenters and Techniques no small app would ever find any use for… For now I’ll have to get good at the basic stuff I guess, I’ve still got some time. What I found very interesting were the Load/Stress “Patterns” Marcin displayed. For example if your application is always busy, or strangely idle – even with lots of request’s comming in etc. It’s something that really makes you think about the app/server and bottlenecks… Sadly I can’t seem to find anything similar about those online – maybe I’m just not searching well enough. I hope to see some of those behaviours while testing our databases, we don’t have multiple application layers in these tests and finding bottlenecks should be easy – it should be, right? ;-) Anyway, I hope to have some fun experiments with our mini-server.

GeeCON 2010

The whole event was also a small GeeCON campain. People got some stickers and [smycze] with GeeCON branding. I’m planing to go there as it seems like an very amazing event… This year it’s in Poznań, and it’s being organized with cooperation of the Poznań and Polish JUGs. I’ll keep you up to date about upcomming Java Events – the next being SFI and then *something special* in April :-) Well then… “Let’s move the Java World!”

Yeah! It’s time for another great JUG meeting. I’ll have to go quite far this time, as it’ll be in Poznań and that’s about 7h by train from Cracow… but at the very moment I saw who was going to be there, that is: Geertjan Wielenga (whose blog I’ve been reading for a long long time and also Romuen Strobl’s pal from the Netbeans team) and Tony Epple, I just knew I can’t miss such a 2-day crash course about NetBeans Platform. I’m mostly interested in EE stuff and didn’t really look all so much into SE apps (just the few while I was very fresh to Java) and this’ll be a great opportunity to see the NBP in action and explained by the pr0s!

It would seem that I’m not the only person who’s excited about this JUG Meeting as during only one day, already 42 out of 45 possible attendands got registered! I already got my Hotel booked and tommorow I’ll buy the train tickets. Oh, and one more great thing  this trip. My girlfriend will some with me so after I code some stuff we’ll check out Poznań – some people told ma that it’s a really nice city. :-)

More information can be found here: (in polish) http://www.jug.poznan.pl/2010/01/bezplatne-szkolenie-netbeans-platform/ or here: http://www.jug.poznan.pl/materialy-ze-spotkan/netbeans-platform-training-2010/ (in english)

—EDIT—

Sadly I wasn’t able to go to this meeting since there were no free places left for students from outside Poznan. I guess thats understandable since they are Poznań JUG, so they want to teach Poznań students more than Cracows students ;-) As sad as that has been for me, something even better came out of it! What? Well, just wait a month or two and I’ll let you know JavaGeeks!

I wasn’t there from the beginning as I had some work to do, but I managed to get there after the “pizza-pause” and listen to:

• Miroslav Kopecky, talking about Matlab in Java (in English).

It was quite interesting to see how MatLab can be used in Java apps to make complex calculations really simple (well… let matlab do the for you basically). I like the idea of exporting plots from matlab directly to JavaScript, thus allowing nice WebApps with heavy math behind them (stock analysis etc.). That said, matlab is closed source as you propably know, and this makes it kinda sucky to develop J2SE apps based on it, as the enduser has to buy matlab anyways to use you program. A solution mentioned is getting 1 matlab license, put it on a server ane make your aplication a webapp – I agree that this is propably the best solution to avoid this “license hell” but it’s sad that there is no other license for endusers of procucts that use matlab as their math engine… Next up was:

• Łukasz Czerpak with the topic: “Swingowa aplikacja rozproszona dystrybuowana poprzez Java Web Start” (technologie: EJB3/JPA, Java Web Start, OpenEJB+Tomcat+Hibernate, Swing Application Framework). (whoa, that’s long)

He talked about his real live experience with an (banking) app that they “ported” to WebStart using GlassFish and then Tomcat+OpenEJB. A nice fact that I learned from this presentation was about how easy glassfish is. …and slow and big… JARs that a user needs to download from JavaWebStart are about 41MB, that’s a lot – since the app talked about was like 300KB. Tomcat on the otherhand is both quicker and smaller – there’s a little more to configure though – but I guess thats a small price to pay. Sadly he didn’t have time to say anything about Griffon which I’m a little interested in lately. It was quite interesting though… :-)

All in all, I liked it and will attend the next meeting in January – hope to be there from the start and not only halfway through as today. ;-)

PS: There was a sad ending for this day for me though. As I really didn’t want to miss even more of this meeting, and so I parked my car where it’s not allowed in order to save some time. When I came back to my car after the meeting my car’s wheel was “locked” (by the police) and got a ticket for wrong parking… So the free JavaCamp didn’t end up being so free for me… ;-)