ACA Blog

ACA Blog

August 2019
« Jul    


Infinite Possibilities

Jan EerdekensJan Eerdekens

November might be a drab and dark month in Belgium, but for me as a Java developer it is THE time of the year because it is the month in which Devoxx is organised. Devoxx is 5 days jam-packed with knowledge that helps a developer like me keep up to date with the current state of the Java universe, but also with what the future will bring.

One of the things that makes Devoxx special is that the event is being held in a cinema complex. This means excellent image, sound and seating. Sometimes even too good as some people manage to fall asleep in the comfy seats. Luckily Devoxx, and this year our own ACA IT Coffee Lounge, provides enough caffeine for most people to keep their energy levels up to get through these very busy days.

A busy work schedule means I can’t go to Devoxx for the full week, but I usually manage to attend the first two conference days and this year wasn’t any different. In this rest of this blog I’ll try to give you a short impression of my favourite sessions of those two days.


The start of the first 2 of the 3 Devoxx Conference days is traditionally a series of keynotes by what you’d call the usual suspects: the Devoxx crew, Oracle, Google and RedHat. Keynotes usually aren’t really technical, so as a developer they’re usually something you have to get through to get to the good stuff, but the Devoxx ones have a good track record and are mostly pretty fun and interesting.

Devoxx Keynote

The first keynote is traditionally given by Mr. Devoxx himself: Stephan Janssen. He started of by announcing that Devoxx again was completely sold out (actually on the brink of being over capacity) which translates into 3500 people and more than 30 companies/sponsors. He followed this with the announcement of the Devoxx Hunt: a game for the attendees in which they have to use their smartphones to find beacons placed all over the venue and city (including -30000 points honeypots). He also stood still by the enormous success of the Devoxx4Kids initiative and Devoxx spinoff conferences in France (4th year and sold out already in early bird) and the UK (3rd year, 50% more people). The Devoxx concept is so much of a success that next year there’ll even be a Devoxx Poland and there even will be Voxxed Days (small 1 day local conferences that might grow into full Devoxx events someday).

And not only Devoxx is a success, but also Parleys the platform on which all recorded sessions are published (and you get access to as an attendee). Even the JavaOne conference is in the process of uploading their talks which means that by the end of the year it’ll contain 5500 presentations and have 500000 users. And now the Parleys platform will even take the next step and courses will be added.

The final announcement by Stephan was that we will also get a new internet home for the Java community: Voxxed. Think of this as something like a TheServerSide for the new century. And of course the inevitable happened and the site went down during the presentation. I guess they forgot to make a sacrifice to the demo gods.

JBoss Keynote

The second keynote of the day was one by Mike Piech of JBoss about xPAAS. He started by describing that we’re currently working in a completely new context from a decade ago. Today IT has to be more immediate, pervasive and aware, which is difficult in a world where innovation (cloud, containers like docker, microservices, devops) is in a constant battle with legacy and JBoss sees their xPaaS offering, OpenShift, as the solution to this. OpenShift is supposed to provide a unified PaaS experience which they then tried to demonstrate by giving a pretty cringeworthy demo by ‘trying’ to do something with memes, but don’t take my word for it, just check this.

Oracle Keynote

Last of the keynotes on day one was by Oracle’s Brian Goetz in which he went over the history of Java up until where we are today with Java 8. He started off with the fact that Java is 20 years old already, but still going strong. So sticking to what got us here in the first place should be a good strategy to evolve Java. This means that they want to add as little as needed while still sticking to the principles of simplicity, readability and transparency. That is why for example generics took 10 years to be good enough to be put in and why we only got lambdas in 2014.

Next he talked a bit about what the future will bring with Java 9. Java will have to run on smaller and smaller devices, security becomes even more important and for the first time with Jigsaw some stuff will change dramatically as some internal APIs won’t be available anymore as will be rt.jar and tools.jar. He even speculated a bit about the direction of Java after Java 9 with Project Valhalla (Value Types, Generic Specialization, Reified Generics, …) & Project Panama.

Brian was followed on stage by Richard Blair and Jasper Potts who gave a short talk about the Internet of Things where lots of different architectures and protocols have to work together (by means of e.g. mesh networking) and demonstrated this with their telematics java car demo.

Google Keynote

The Google Keynote that started off the 2nd conference day was a bit different than usual as it was a nice combination between technical and design, instead of almost all tech(nical), as they presented Google Papercraft. Papercraft is their new project that uses the concept of Material Design to try and provide a flexible approach to create a coherent cross platform experience. It has its roots in Project Kennedy (unifying the look of their webapps) and Project Holo(unifying the look of their mobile apps). With Material Design they’re now trying to take the next step where they unify the look of all their applications, web or mobile. They do this by using a few key concepts:

To me it kinda looked like Google’s version of Twitter Bootstrap, but on steroids and not only for the web.

Modern Web Architecture

Next up was a talk by the always entertaining and seriously funny Ted Neward about web architecture. Like a lot of the other talks I attended this one to started off with a look at history, in this case the history of the web/web applications.

This journey through time started off with Project Xanadu (which Wired magazine described as “he longest-running vaporware story in the history of the computer industry”) which can be thought off as the origin of Hypertext. A concept that was later made into something that actually works by the famous Tim Berners-Lee. This work resulted in the 90’s in the first generation of the web, which consist of mostly static content of which he gave a very appropriate example: the original Space Jam website (which is remarkably still online).

In the second generation of the web we got some more dynamic sites using technologies such as CGI, Java applets and Flash to retrieve data from somewhere, show it to the user and allow for some interaction. This in time evolved into technologies such as PHP and Java servlets to create more complicated web applications. These and other technologies were able to show pretty complicated user interfaces to the end users, but after a while it became clear that there was a growing set of users that is more interested in the data that is being made available by your interface than the interface itself. This resulted first in various screen scraping technologies, but later in actual technology to make the data directly available such as web services and more recently JSON/REST. But even with the latest web architectures there’s still problems such as link rot, security and redundancy/resilience.

The talk was rounded off with a look at what’s next in Modern Web Architecture:

Groovy in the light of Java 8

The last talk of day 1 for me was by Guillaume Laforge about Groovy. In it he took a hard look at the necessity of Groovy in a Java 8 world. With Java 8 there now seem to be a lot of possible redundancies between Groovy and Java 8:

For each of these he showed that Java 8 now indeed has similar functionalities (with maybe even Groovy as inspiration) that Groovy has had for years. Even with these similarities, Groovy still has enough leftover functionality to be very useful alongside or in combination with Java 8:

The message he closed the talk with is that Groovy still has its uses will continue to do so because the Groovy team will always continue to innovate like they’ve done in the past.

Modern Enterprise Java Architectures with Spring 4.1

On day 2, 1 of the Spring founders, Juergen Hoeller, gave a nice state of the union of the Spring world with regards to Java 8 (one of the main topics of this year’s Devoxx). He started off with the fact that in the quickly changing Java landscape, with its new deployment models (docker, embedded servers, …), non-DB datastores (NoSQL, Graph DBs), lightweight messaging, … Spring needs to keep up. It does this by upgrading its baseline to Java 6, Servlet 2.5 and JPA2. While this seems to be not as ‘new’ as you would expect, it was done with (backwards) compatibility in mind, but with a focus on Java 8, Servlet 3.0 and JEE7 support. So you can still use most of the newer Spring 4.1 on older environments, but everything will also work in an environment based on the latest and greatest.

The highlights of Spring 4.1 are:

His talk was rounded off with a short code demo using Spring Boot which served mainly to demonstrate the ease with which an application can be created using

Java 8, 9 and beyond – Ask the experts

Usually during Devoxx there’s always some sort of expert panel and this year was no different. The term ‘panel’ in this case might be a slight overstatement with only 3 people on it: Brian Goetz, Paul Sandoz and Stuart Marks. While I don’t want to take anything away from Paul or Stuart, in my humble opinion you could put Brian on stage by himself and he’ll be able to keep a room full of Java devs entertained for a couple of hours. The panel was pretty freeform as there wasn’t anything prepared and all questions were taken live from Twitter using the hashtag #JavaQ, but this actually served its purpose pretty well and there wasn’t a dull moment and the session was over way to quickly.

The main takeaways of various topics the 3 talked about were:

The panel was rounded off by asking all panel members their most hated and most wanted Java feature. The most hated feature was almost unanimously serialization or as they put it: the gift that keeps on giving. The most wanted features were: Tuple/Pair and multi value streams/returns.

Honorable mention: The Codeless Code

My last session of day 2 at Devoxx was The Codeless Code by Martijn Verburg. He might not have been the speaker that was supposed to give the talk, but his natural style (and outfit) made him the perfect guy to deliver this talk. He is usually referred to as the Diabolical Developer, but in this talk he took on the role of a Java-Fu Master that explained the most common pitfalls of our daily working life using very appropriate Chinese Kung-Fu parables. As I’m not nearly good enough to reproduce his fantastic tales of how apprentices of the various clans (Crawling Spider/Flying Monkey/etc…) get enlightened by their masters I can only point you to the excellent source material he used:


In the two short days I was at Devoxx I had tons of fun absorbing a lot of new information. The only real problem I have is that there is so much interesting stuff to see, learn and do that I’d need to clone myself to be able to follow all the sessions I would’ve liked to. So in my opinion, even when placed against the original Java conference, JavaOne in San Francisco, Devoxx is still the Java conference to beat. If you have developers that want to go, send them, as it is the best value training they can get on a yearly basis.

And to end this blogpost I’d like to point you to the must see Ignite Session by Stuart Marks (that I missed) with the mysterious title: OpenJDK Development Using Tactics from Game of Thrones


Belgian Java and Liferay developer with some weird interests, eternal complainer, atheist, skeptic and geocacher.