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Vaadin meetup

I attended Vaadin meetup with a few colleagues on a way to JFokus 2013 and thought I should share my notes of the two. First post is about vaadin meetup that took place on a cruise from Turku to Stockholm.

I made notes of three presentations and one of them I had high expectations. There were also two other presentations that I didn't make any notes of.

Vaadin 7

Vaadin released Vaadin 7 framework the same day that the meetup was on so they had a presentation where they told about new features and future plans. I'm more of a backend programmer than UI programmer so my notes of this were pretty brief but here it goes.

Whats new

  • Servlets and HTTP-sessions are controllable by the programmer
  • Multiple UI classes
    • e.g. One for web browsers and one for mobile web browsers
  • GWT is now build-in
  • Support for external JavaScript modules

What to expect in the future

  • Faster relase cycles
    • maintenance release every two weeks
  • Dynamic CSS injection
  • Vaadin CDI, their own depency injection system
  • Vaadin charts, for drawing nice charts


This was a project ordered by Helsinki university and it was developed by a company called Arcusys. It's some sort of feedback system. The interesting part of this presentation was why they chose Vaadin framework for the UI. They chose it because it could programmed with Java or Scala and the developers didn't need to have any knowledge of web technologies like HTML, CSS or JavaScript.

Modern software development anti-patterns

Martijn Verburg, Diabolocal developer, had a presentation of software development anti-patterns. This the presentation that I really wanted hear he also had the same presentation later at JFokus. I had high hopes for this presentation and it didn't let me down. I'm just going to write a few buzzwords and notes here and the rest is available on Martijns slides and video filmed at the meetup.
  • Mortage-driven development
    • Write code to pay your mortage and make sure anyone else can't understand your code
  • Distracted by shine
    • Always use the latest and greatest
  • The deity
    • Huge classes e.g. Java class with 140k lines
Those were anti-patterns but he also gave tips how to avoid anti-patterns. 

One of the things he said is something in my opinion every developer should understand and remember. The anti-pattern was CV++ meaning that you try all the new frameworks and tools just so you can put a new line in your CV when instead you should be good at the principles.

So what does that mean. It means know the principles of software developent because languages, frameworks and tools change and evolve all the time but if you know hte principles you can always learn a new language or learn howto use a framework you haven't used before.

All the presentations of Vaadin meetup were filmed and uploaded to youtube. Links can be found at Vaadin meetup website

On the next two posts I'll be what I learned in JFokus 2013.


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