Java: Still in the Zone

This week was the JavaZone conference in Oslo, which I was fortunate to attend again. Looking back, this is the seventh time I've presented at this conference.

As with other Java conferences that have been running for many years, this organization has become flawless. That said, I know the organizers put in an incredible amount of hard work to make everything work well. Just because it runs so well doesn't mean it requires little effort!

As usual, the event was packed, which is a clear indication that Java is still hugely popular in Norway (where most of the attendees come from). We see surveys like Tiobe and Red Monk, but it's good to see real people keen to find out more about Java and its associated technologies.

I really lucked out at this year's conference. My session was the first on day one at 9.00am, and I talked about current and future Java, both from a technology and delivery perspective. The changes to JDK release cadence, availability of updates, and long-term support are causing some confusion. My goal was to clarify what recent changes would mean to the choices people had to deploy Java in the future. I made use of the description I've used before: Java is Stable, Secure, and Free. Now, however, you must choose two out of free.

I was a little apprehensive that being first thing in the morning the attendance might have been reduced, as people gradually arrived by mid-morning (something I've seen at other conferences in the past). I needn't have worried; my session was packed. JavaZone provides a unique presenting experience for certain sessions. I was standing on a platform suspended over the main arena by nice solid looking chains, facing the audience in the auditorium seating. Just don't step back too far!

Having completed my presentation, I was then able to focus on getting as much out of the conference for myself as possible. I did this in three ways:

1. Walking around the exhibitor area and talking to people about what they were doing and what technologies they were using. I'm no salesman, but I did mention what Azul is doing with Zulu Enterprise, where it seemed relevant and might be interesting.
2. Attending sessions. I don't often get time to do this much at conferences, and even when I do, I sometimes struggle a bit to find sessions that I want to attend. This was not the case at JavaZone. Aside from listening to my colleague Doug Hawkins talk about our ReadyNow! product (always good to get more knowledge about that), I found a number of interesting sessions:
   • Chris Thalinger spoke about the Graal JIT compiler and how it's used at Twitter
   • David Simms described the low-level ideas for the design and implementation of value types in Project Valhalla
   • Oleg Šelajev gave a fascinating overview and demonstration of the Graal VM (Graal seems a bit overloaded, since it's really just the JIT. The VM makes use of the Truffle framework in conjunction with the Substrate VM. It might have been better to give the whole thing a new name).
3. Talking to people. The most valuable thing I get out of conferences is often the conversations I have with people in the public areas, during the speakers' reception, and other social events. It was great to exchange ideas with people about what we could do to make Java even better and give developers more of what they want. Java is more open than ever, with more ideas being contributed to the OpenJDK project through JEPs from outside Oracle. Even Google contributed a JEP to JDK 11, which shows how inclusive the project is. Some ideas were more practical than others. I had a very thought-provoking discussion on whether we could change the JVM specification to eliminate restrictions on lazy classloading and initialization. This could potentially improve the startup performance of applications, especially with techniques like the ones we use in our ReadyNow! feature in Zing. I need to talk to our engineers in more detail about this; I may well be missing some critical aspects of this idea.

JavaZone was a great conference: great sessions, great presenters, great venue (and great food!). I sincerely hope to go back again next year.