Since this year’s Java Day Tokyo 2015 is about to happen, I figure I should post my article about last year’s event. Unfortunately I won’t be able to attend this year. But last year I traveled to Japan for Java Day Tokyo 2014 and for a Japan Java User Group event. The trip was packed with events. I brought my family along with me, and fortunately we did have a couple days to travel around Tokyo to relax and do some sightseeing.
JJUG CCC 2014 Spring, 18 May
The first event was the JJUG CCC Spring 2014 (Japan Java Users Group, Cross-Community Conference). This is a twice-per-year gathering of several JUGs from around Japan where they stage a full-day conference. It turned out that I was one of the keynote speakers! I was told there were over 300 people attending, making it one of the biggest JJUG events ever. Wow, I’m honored.
My presentation was Overview of Java 8 Lambda and Streams, which covered not only those topics but also default methods and method references. That’s a lot to cover, and I couldn’t go very fast because I had to pause after every sentence for consecutive translation. Still, people said they enjoyed the presentation and that they found it helpful.
Here are some pictures Yuichi Sakuraba took at the event. (He seems to be the designated conference photographer in Japan, when he’s not busy taking pictures of food.)
Yuichi has posted a Flickr photo set of the entire event, including a few more of me.
Java Day Tokyo, 22 May 2014
This was the main event. It was jam packed with sessions, including a set of keynotes in the morning, and five tracks in parallel in the afternoon. Here’s the agenda, and here are slides and videos from the subset of sessions that were recorded. I had two sessions in the afternoon: the first on Java 8 Lambdas, and the second on Java 8’s new Streams API. Here are some pictures I took during the keynotes.
Nandini Ramani (former VP, Oracle Java Platform Group) and Shin Ishiguro (NEC) showing off the NEC PaPeRo robot featuring Embedded Java SE:
Stephen Chin and Cameron Purdy demonstrating the Lego Duke balancing on two wheels:
That evening after a full day of sessions, there was a two hour “Ask the Experts” panel and I was on the panel. David Buck (Oracle JVM Sustaining) was pressed into service doing consecutive translation in both directions between the audience and the panelists. I think he did quite well considering he’s not a professional translator.
Not surprisingly (as Java 8 had just been released) most of the questions were about Lambdas and Streams. There were some pretty good questions. One question asked about some details of how lambdas are implemented. I replied that I’d try to be brief and hold my remarks to under half an hour. That got a laugh out of the audience (a Japanese audience — a first for me!). David did pretty well translating my answer, until I got to the part about the “lambda metafactory.” I’m not the real expert at this, though. Brian Goetz is, and he’s given a talk called Lambda: A Peek Under The Hood that explains the lambda implementation in great detail.
The following day, (not officially part of the conference) we had a hands-on lab in the Oracle offices where we let participants try their hand at a set of exercises that can be solved using Java 8 Lambdas and Streams. This is similar to labs we’ve had at JavaOne and Devoxx and other conferences:
Like most labs, after a brief introduction, most of the participants went heads-down and worked steadily on the problems. They must have been pretty good problems, since most people were still working on them when we ran out of time!
I’m sad to be missing this year’s Japan event. Make sure you go if you get a chance. It looks like it’ll be as good if not better than last year’s!