10 November 2022

After several years of “silence”, it has been announced that the most popular conference in the Java world, JavaOne, is brought back to life! Yes, JavaOne is back, and although its first reincarnation could use some tweaking, it is a great start to make it the premier conference to kick off the conference season.

Of course, OpenValue as a frequent conference speaker could not miss the opportunity to enjoy such an incredible and magical comeback moment - this time in great numbers!

Our very own Miroslav Wengner and Benedikt Neumayr talking about “Simplified Design Patterns” in Java 19 were joined and supported by further OpenValue colleagues raising the total number of the wolfpack to a Las Vegas classy and round 11.

Certainly, our mission was not that of just playing the role of a groupie - at OpenValue we like to gain and share knowledge, therefore we tried hard to dive into as many interesting topics and acquaint with as many drivers as possible.

We asked some of our colleagues to share their thoughts and impressions below, so that you get an idea on what drives us and what to possibly to expect from us at the next conference talk (spread the word, sharing is important!) - below is what they agreed to share, because we want to honour the well known saying: “what happens in Vegas, stays in Vegas” (some things happened in Vegas should stay in Vegas, the good news is that no one got married unexpectedly).

Alexei Bratuhin: It’s been a while since I last attended a conference or a meetup, so no wonder that an event of that scale left a strong impression on me. Luckily I was wise enough not to book my schedule with talks, sessions and labs completely, but instead leave some time to wander around the location and get to know other people.

That kind of strolling turned out to be very fruitful for me

  • first, i stumbled upon Henri Tremblay to serve him as a rubber duck (see https://en.wikipedia.org/wiki/Rubber_duck_debugging) during a bugfix for EasyMock (which as I - and probably many of you - didn’t know, is the precursor of the very widely used and adopted Mockito testing framework (https://site.mockito.org/). To be able to get some insights on the history and different approaches in both frameworks was very insightful for an information-hungry like me.
  • second, i hooked up one of my colleagues with Jakarta EE guys working together with Ivar Grimstad on the new Jakarta EE starter project (similar to code.quarkus.io). Could this (hook-up) be the new ray on the GitHub activity overview graph, next to commits, issues, reviews and pull requests?
  • third, i managed to find one of the RedHatters (believe me, it wasn’t easy; yes, there were many people attending; no, not everyone from RedHat actually wears one on a daily basis) working on Quarkus (which I’m a fan of) and get a review of my upcoming brown-bag-session “10 things I like about Quarkus”.

Some other event highlights were

  • well-structured and thoroughly prepared labs on GraalVM and Project Loom;
  • announcement about microTx, which could greatly simplify implementing the saga pattern (distributed transaction) in average microservice-based projects;
  • talking to Graeme Rocher regarding differences between Micronaut and Quarkus (i’m a fan of Quarkus, but i’m also curious) and grasping the roots of SpringData query method naming, coming from Grails and Groovy’s string powers;
  • listening to Jeff Smith’s talk about API design and development - you’re going to love the calm humorous delivery;
  • taking notes of hints regarding Java performance tuning in Kubernetes provided by Bruno Borges - fortunately the slides are available online;
  • and of course absorbing the unbelievable amount of energy irradiating from Erin Schnabel during her talk about testing the microservices.

All in all a wonderful experience pushing myself to share the knowledge I possess with others - I hope to be able to use the impulse until the daily routine absorbs it completely.

Christoph Ahlers: About one year ago, I joined OpenValue and I would never have imaged that I would be visiting a conference in Las Vegas in person! But OpenValue offered my colleagues and me this amazing opportunity!

At the conference, I managed to visit 17 talks and meet a few incredible people. The most famous one might have been Bruno Souza. This Java Champion is on a quest to inspire everyone to improve himself, to become visible in the community and spread our knowledge. He was very inspiring! Another remarkable person that you might have seen already was Nicolai Parlog. You might know him already due to his hairstyle or due to his awesome Java Newscast on YouTube! He talked about the module system and provided guidance to solve issues when adapting it.

Looking back at the wide range of topics I listened to, the talks taught me a lot. Now I have seen a few best practices, especially regarding the recent additions to the JDK. But particularly interesting were some recent engineering achievements like improvements to ZGC who receives a new variant called Generational ZGC. It looked like it will overshadow the current version. But I am especially thankful to learn about OpenJDK CRaC which allows us to load a “hot“ VM. That means superfast startup like AoT compilation in the cloud, but with all the benefits and peak performance that Hotspot brings along! It is the best of both worlds! Incredible!

After a long flight back and some time to digest the impressions, I truly only regret one thing: I, a Formula 1 fan, missed Max Verstappen’s brief visit at the venue! Oh, maybe next time! My next conference visit will be at Javaland. In the meantime, maybe you should become visible and join us at a meetup; I am sure Bruno would like that!

Miroslav Wengner: Lots of meetings, booths and talks to attend, I was running everywhere. I enjoyed all the talks I attended, from Observability by DataDog crew to core members of various Oracle Java teams, followed by Gradle or Azul crew, RedHat, IBM and Microsoft individuals, and more…

2022 Java Community Process/ Java Leader meeting: Discussing future of Java development and getting deeper insides into the project Looms, Amber, Valhalla or Panama. There we also discussed the latest improvement in JVM runtime and hotspot.


  • Data Parallel Programming in Java Using the Vector API by Adam Pocock from Oracle and Paul Sandoz nicely touched kind of scientifically how to use the Vector API for the computational problems useful in the field of ML or Machine Learning.
  • Sequenced Collections by Stuart Marks nicely described current pitfalls with the Collection framework and necessity to consolidate it.
  • Collections Connection Rebooted by Stuart Marks has driven very nice discussion about challenges of current Collection Framework available in JDK.
  • Data-Oriented Programming with Records, Sealed Classes, Text Blocks, and More presentation delivered by Gavin Bierman from Oracle Java Platform groups has nicely summarized the lately added feature into the JDK that improve data driven programming approach
  • Project Loom Hand-On Lab served very nice real experience with preview features like Virtual Threads (JEP-425) or Structured Concurrency (JEP-428) lead by David Delabassee. Together with experience of OracleCloud
  • Teaching Quantum Computing in a Block World was a very nice, not only, introduction to the challenges that quantum world brings to us. James Weaver has shown on examples some basics and advanced challenges with solutions.

Yevgeniy Sanitskiy: To be honest, it is quite difficult to describe in words the feelings that I experienced during this fascinating journey. I have never had to meet such high-level specialists in one place at the same time. I was given by OpenValue a unique opportunity to personally see famous people whose work I have been familiar with for a long time.

The topics for discussion were so diverse. Starting from the Java itself (this is #JavaOne conference, after all), new features, techniques, code cleaning and optimization, best practices and ending with an overview of AI technologies for analyzing the state of forests, tree health and controlling the woodworking industry. Any sophisticated listener was undoubtedly satisfied.

I would especially like to mention the organizers of the event. Everything was just great. A lot of work has been done to make visitors from all over the world feel as comfortable as possible. And if someone had difficulties, for example, finding a specific room, then very friendly and always smiling consultants were always ready to help.

The only thing to regret is that sometimes it was not possible to visit all the sessions of interest. Unfortunately, some of them took place at the same time and then I faced a difficult choice - where to go and what should I skip. And, sadly, videos are only available for relatively big sessions.

All the speakers performed superbly, but some of them were especially memorable:

  • “Functional Programming Idioms in Java” by Venkat Subramaniam: just an incredible amount of charisma, as well as clever remarks about why many Java programmers do not know how to use functional programming;
  • “Pattern Matching: Past, Present, and Future” and “Data-Oriented Programming with Records, Sealed Classes, Text Blocks, and More” by Gavin Bierman: his professionalism and ability to present information in a clear and structured way are simply fascinating;
  • “Beyond Senior Java Dev: The Next Steps for the Technical Career” by Bruno Souza and Ruslan Synytsky: very useful thoughts and personal experience of Ruslan about how a developer can choose his way. How to finally figure yourself out - management or staff-plus engineer;
  • And I want to thank again James L. Weaver JavaFXpert for signing a “Quantum Development with Qiskit” book for me.

In my opinion, this event is very important for our entire community. This platform provides huge opportunities for absolutely everyone. Here you can not only gain new knowledge, but also meet interesting people and negotiate a profitable partnership. And of course, have a good time, because this is Las Vegas!

Sebastian Konieczek: This was my first JavaOne, and what a location it was! Las Vegas and the conference rooms at the Caesars forum where awesome. Thank you again for the great organization and the awesome event JavaOne and thank you OpenValue for giving me the opportunity to be there ❤️

I visited a lot of talks of some awesome speakers. For example, I was attending Nicolai Parlogs talk about “Java Modules in real live”. It was really inspiring and made me think about trying to introduce it on my next suitable project. It made me even wonder why the Java modules system is so rarely adopted by the community and what benefits it may have for pure server applications like restful microservices.

Another nice talk to mention was the talk about “Data-Oriented Programming with Records, Sealed Classes, TextBlocks and More” by Gavin Bierman. He showed some awesome examples on how these cool java features can help you in your daily business.

A talk from another world was “To Production and Beyond: Metrics with Micrometer“ by Jonatan Ivanov and Erin Schnabel. Not only was at an interesting talk, but the energy brought to the stage by Erin Schnabel was more than inspiring. You really feel how passionate she is about the topic and her profession and that is the “ingredient“ that makes a good talk great.

Also, the possibility to meet so many well known and awesome speakers and java champions in person made me really feel like being a part of the community and gave me motivation contribute to the community, share my experiences and may be, some day, speak at awesome conferences too :simple_smile:

So no more to say than hopefully I will get the chance to visit you again #JavaOne, it was a pleasure!

All in all it was a fabulous experience - thanks to the organizers, volunteers, champions, JUG-leaders and many more who made this event and Java possible.

Getting to know new people, reconnecting with old friends (Azul!) and simply having fun while enjoying the information being served to us directly while enjoying wonderful “Javaritas”. So until we meet again, we say - long live Java and Prost!

Sebastian Konieczek

Sebastian is a passionate Full Stack Software Engineer from OpenValue Düsseldorf. He is an expert in the requirement analysis of complex systems in the field of investment advice and pension provision, but his long years of experience he covers the entire software life cycle from analysis to commissioning and support. Sebastian's interests lie in architecture and design issues, but coding remains his passion. When there is time left over from work and family, he does weight training and fitness, plays games and enjoys working on hobby projects.

Miro Wengner

Miro is a member of the JCP program for very long time. He contributes actively to the OpenJDK, Java Mission Control/Flight Recorder project. His focus is on java performance and maintainability. Miro has also contributed/is contributing to various another open-source project such as OpenTracing, Pi4J and etc. He is also co-author of Robo4j project which has been awarded by DukeChoice Award 2017. Miro has been recognized as JavaChampion, RockStar speaker. Aside of his daily duties as a Principal Engineer at OpenValue he shares his knowledge over conferences (JavaOne, CodeOne, Devoxx, GeeCON etc.) and blogging. Miro has been Elected to Java Community Process (JCP) - Executive Committee to help guide the evolution of Java technologies.

Christoph Ahlers

Christoph is one of OpenValue's Senior Fullstack Developers with a lot of experience in different projects and different technologies. He has a passion for complex issues, is always looking for new challenges and likes to share his experiences. Besides his daily work, he is a renowned StarCraft II / Heroes of the Storm modder. From his hand are: GameHeart's Obs UI, Diablo Mortal Shroud in StarCraft II and AhliObs in Heroes of the Storm.

Yevgeniy Sanitskiy

Yevgeniy is highly experienced and highly motivated software engineer from OpenValue Munich. He has more than 10 years of experience in structuring, developing and implementing interactive websites and applications. Yevgeniy is a team player who is committed to the project goals and sets the right priorities. His main areas of expertise are backend, microservices, DevOps, cloud computing, high load systems, application architecture and infrastructure design. He is passionate about expanding the possibilities for business through the use of technology. He is constantly developing his expertise with a great thirst for knowledge and he enthusiastically shares his experience with the team.

Alexei Bratuhin

Alexei is a software engineer / IT consultant since over 15 years, specializing in Java. He has vast experience in application design, development, operations and support in multiple domains including information security, telecommunications and automotive. He is also a passionate contributor to open-source whenever he can - both in his private time and as part of the project work