Foojay.io | Friends of OpenJDK and Java Programming

The Foojay Java User Group World Tour has already brought us to a lot of different countries all over the world. But for this episode, the host decided to stay at home. The Belgium JUG (BeJUG) started in 1997 and was the birthplace of Devoxx, Devoxx4Kids, and VoxxedDays. And in our capital Brussels, we can join Brussels JUG (BruJUG), since 2010.

So there’s a lot we can talk about to learn more about communities and conferences!

Guests

Olivier Hubaut, BruJUG

• https://www.linkedin.com/in/olivierhubaut/ 
• https://mastodon.top/@ohubaut

Stephan Janssen, founder BeJUG, Devoxx, Devoxx4Kids, Voxxed

• https://www.linkedin.com/in/stephanjanssen/
• https://twitter.com/Stephan007

Tom Cools, AntwerpJUG, BeJUG

• https://www.linkedin.com/in/tom-cools-17547548/
• https://twitter.com/TCoolsIT
• https://mastodon.social/@TCoolsIT

Podcast host

Frank Delporte

• https://www.linkedin.com/in/frankdelporte/
• https://foojay.social/@frankdelporte
• https://twitter.com/FrankDelporte

Links

• https://www.meetup.com/belgian-java-user-group/
• https://www.meetup.com/BruJUG/
• https://devoxx.be/
• https://events.voxxeddays.com/

Content

00:00 Introduction of the topic and guests

02:19 History of BeJUG and the start of JavaPolis (Devoxx)

06:00 How BruJUG (Brussels) started and evolved

• https://www.hanselman.com/blog/dark-matter-developers-the-unseen-99

08:35 Tom as the winner of the bad timing award with AntwerpJUG

10:35 Impact of Covid on Devoxx and BruJUG

18:09 How BeJUG got restarted in 2022

• https://github.com/BeJUG/bejug.github.io 
• Video: "Transitioning into Tech: The Journey of a Senior Junior Developer by Ibrahim Dogrusoz"

27:05 How BruJUG attracted new speakers + tips for new speakers or new talks

31:32 How Devoxx4Kids grew to a worldwide event

36:03 The tools developed and used to manage Devoxx

41:13 About the name change from JavaPolis to Devoxx and the franchising

46:14 Future plans for Devoxx, BruJUG and BeJUG

51:14 CFP for Devoxx and how reviewers can find sessions for their JUG

54:16 Outro

How do you get the maximum performance out of your Java application? And how to use profiling to find the bottlenecks? Let's learn it in this podcast!

Java profiling is a crucial technique for measuring and improving the performance of applications. It helps identify bottlenecks, memory leaks, and other application performance issues. There are various challenges with using Java profiling, and the need for profiling depends on the complexity of the application and the performance requirements. Let us learn more about the challenges, different profiling approaches, and when to use Java profiling to reach the best performance with our Java code.

Guests

Chris Newland

• @chriswhocodes
• mastodon.social/@chriswhocodes
• chriswhocodes.com/

Marcus Hirt

• @hirt
• hirt.se/blog/ 

Heinz Kabutz

• @heinzkabutz
• linkedin.com/in/heinzkabutz
• www.javaspecialists.eu/ 

Podcast

Host: Marcus Lagergren

•  @lagergren

Production: Frank Delporte

•  @FrankDelporte
•  foojay.social/@frankdelporte 

Content

00:00 Introduction of the host and guests

• jitwatch 
• jacoline
• foojay.io/command-line-arguments 
• Book Optimizing Java
• JCrete

10:42 History of Java and how performance was a challenge in the beginning

14:21 What is profiling? What should be profiled? What is good profiling?

28:44 What you should learn about profiling and performance

31:43 Impact of the different garbage collectors on performance

32:59 Performance and profile should focus on the right requirement for your system

34:39 Ergonomics in the JVM and tunes itself for the system it is running on

• mail.openjdk.org/pipermail/hotspot-dev/2023-May/074325.html

39:49 What are current important evolutions and upcoming coming or required changes in profiling?

43:19 Break-throughs in Stop-The-World approaches

46:43 Minimize the number of JVM flags you use

• https://jacoline.dev/stats 

56:47 About Errors and Exceptions

58:30 The current runtimes and operating systems are very forgiving

• https://openjdk.org/jeps/312 (Thread-Local Handshakes)
• https://openjdk.org/jeps/444 (Virtual Threads)

1:04:26 Is profiling becoming less relevant?

• foojay.io/today/continuous-production-profiling-and-diagnostics

1:10:20 Conclusion

Grab your Lego and robots, and let's talk about STEM, STEAM, and programming for fun!

As a developer, we all get frustrated occasionally when a bug messes up our schedule, and we have to dive deep into the code to find a solution. But still, many of us keep coding in our free time as we love to do it and want to create amazing stuff. In this episode of the Foojay Podcast, we talk to volunteers from different organizations where coding is used to inspire children to become engineers or at least learn to make good use of computers and the tools around them.

Guests

• Jeanne Boyarsky
  • Twitter @jeanneboyarsky 
  • https://www.selikoff.net
  • Mastodon @jeanneboyarsky
• Monica Beckwith
  • Twitter @mon_beck
• Igor De Souza
  • Twitter @Igfasouza

Podcast host

• Frank Delporte 
  • Mastodon @frankdelporte
  • Twitter @FrankDelporte

Content

• 00’00 Intro
• 00’43 Introduction of the guests
• 03’00 What is First?
  • First Inspires
  • FRC Robot reveal
  • FLL Events
  • Televic Smarties at FLL
• 06’43 What is CoderDojo?
• 07’46 Impact on your career by volunteering
• 09’00 Impact of these organizations on STEM education
  • Scratch 
• 14’00 The rule of three
  • Code Chica
• 16’48 Girls-only events 
• 24’13 What we learn from volunteering for our job
  • Microbit
• 28’16 Technology that can inspire the most
  • Particle
  • Onshape
• 36’09 Participants becoming coach
• 37’58 Java on small platforms like Raspberry Pi 
  • LCD Display
  • Potentiometer
  • Micronaut
  • Quarkus
  • Book #JavaOnRaspberryPi
• 43'39 Java in education
• 47’15 STEM versus STEAM
  • Nervous Jessica
• 53’37 Other interesting STEAM topics
  • Coolest Projects
  • Formula Pi
  • Pi Wars
  • Astro Pi
  • First Inspires
  • CoderDojo
  • Code.org
  • Documentation drive of CoderDojo Belgium
  • Microsoft TEALS
• 59’45 Outro

Once a month, the Foojay Podcast virtually visits a JUG to talk with the people behind it. SouJava, the Brazil JUG, was founded in 1999, and according to Wikipedia, it’s recognized as the world’s largest Java User Group with 40,000 members! There’s a lot we can learn from the people who achieved this.

Guests

• Otavio Santana
  • https://twitter.com/otaviojava
  • https://www.linkedin.com/in/otaviojava/
  • https://www.youtube.com/@otaviojava
• Maximillian Arruda 
  • https://twitter.com/maxdearruda
  • https://mastodon.social/@maxdearruda
  • https://www.linkedin.com/in/maxarruda/
  • https://linktr.ee/maxdearruda
• Bruno Souza
  • https://twitter.com/brjavaman
  • https://code4.life/
  • Free book: http://jav.mn/bestyear

Podcast host

• Frank Delporte 
  • @[email protected]
  • https://twitter.com/FrankDelporte

Links

• http://soujava.org.br/
• https://www.meetup.com/SouJava/
• https://en.wikipedia.org/wiki/SouJava

Content

• 00’00 Intro
• 00’26 Introduction of the guests
• 02’39 History of Java and SouJava
• 08’03 About working on open source projects and the relationship with JUGs
• 12’55 How Max became part of the JUG organizers and how to incrementally improve your skills
• 23’38 Impact of Covid and the advantage of in-person meetings
• 28’20 The best ways to grow as a developer, the spiral of growth
• 51’29 Trying to get back to the “new normal” with the JUGs
• 01h01’12 Conclusions

Functional programming, it seems you either love it or you hate it. But, like everything in software engineering, it is a trade-off. So for today, let's focus on the good, the bad, and the ugly parts of Functional programming.

Guests

• Alejandro Serrano, Software Engineer at 47 Degrees, author of "Practical Haskell", "The Book of Monads", and "FP Ideas for the Curious Kotliner"
  • https://serranofp.com/
  • https://twitter.com/trupill 
  • https://www.linkedin.com/in/alejandroserranomena/ 
• Deepu K Sasidharan, JHipster co-lead, Java Champion, Staff Dev Advocate @ Okta, Java, JS, Rust, Cloud Native Advocate, Author, Speaker
  • https://twitter.com/deepu105
  • https://mastodon.social/@deepu105 
  • https://deepu.tech/ 
  • https://www.linkedin.com/in/deepu05/ 

Podcast 

• Host: Ties van de Ven
  • https://www.tiesvandeven.nl/
  • https://twitter.com/ties_ven
  • https://www.linkedin.com/in/ties-van-de-ven-a24480a/
• Producer: Frank Delporte 
  • https://twitter.com/FrankDelporte 
  • https://foojay.social/@frankdelporte 

Links

• https://foojay.io/today/7-functional-programming-techniques-in-java-a-primer/ (Deepu)
• https://foojay.io/today/the-problem-with-functional-programming/ (Ties)
• https://www.baeldung.com/java-functional-programming 
  
  

Content

• 00’00 Intro
• 00’17 Introduction of the guests
• 07’40 What is functional programming (FP)?
• 11’50 The same problems exist in FP and Object Oriented Programming
• 13’50 Academic approach to programming
• 17’54 Who of the guests is a FP purist?
• 22’25 Understand the “Why”? Why use FP?
• 28’11 The costs of FP
• 30’57 When to learn FP
  • https://www.baeldung.com/java-monads
• 42’43 What is the future of FP?
• 50’41 Outro

Many developers spend a lot of their time on side projects. It’s an opportunity to learn new techniques and get involved in communities. But sometimes, it can also lead to a new job. Or even starting a business based on such a project. Today we are talking to people who achieved such a transition and became famous and rich, or at least some of each…

Guests

• Tim te Beek
  • https://twitter.com/TimteBeek 
  • https://docs.openrewrite.org
  • https://www.moderne.io
• Maarten Mulders
  • https://twitter.com/mthmulders 
• Lukas Eder
  • https://twitter.com/lukaseder
  • https://www.jooq.org/

Podcast host

• Frank Delporte 
  • https://twitter.com/FrankDelporte 
  • https://foojay.social/@frankdelporte 

Content

• 00’00 Intro
• 00’31 Introduction of the guests
• 02’28 What projects are the guests working on?
  • https://maven.apache.org/
  • Maven Central Search: https://github.com/mthmulders/mcs 
  • https://foojay.io/today/introduction-to-maven-toolchains/
  • https://docs.openrewrite.org
  • https://www.moderne.io
  • https://www.jooq.org/
  • https://foojay.io/today/5-great-reasons-to-use-jooq/ 
• 06’34 How Tim got a job at Moderne
• 08’23 The connection between OpenRewrite and Moderne
• 09’23 How jOOQ became a company
  • https://www.oreilly.com/library/view/the-cathedral/0596001088/
  • https://scala-slick.org/
  • https://foojay.io/today/vaadin-and-jooq-match-made-in-heaven/
• 14’44 Building a product is more valuable compared to offering support
  • https://entreprenerd.lowagie.com/index.html
• 21’22 About open-source licenses
• 23’48 Why and how Info Support allows Maarten to work on open-source within working hours
• 27’47 What you can learn from an open-source project
• 28’54 Does every developer have to do be an open-source contributor?
• 32’13 Becoming rich thanks to open-source? Projects versus Products
  • https://s.apache.org/for-the-grabs_maven
• 48’33 About the Fosdem talk about OpenRewrite
  • https://foojay.io/today/foojay-io-at-fosdem-2023-trip-report/
  • https://fosdem.org/2023/schedule/event/migrations/ 
• 48’53 Benevolent dictator for life and how to make money from a programming language
  • https://en.wikipedia.org/wiki/Benevolent_dictator_for_life
  • https://business.jooq.org/
• 51’22 Outro

The Foojay Podcast Java User Group World Tour has already brought us to the UK, US, Dubai, and Japan. Today we travel back to the US to learn more about the Atlanta JUG, mainly because this week, they are organizing the DevNexus conference! Let’s learn about the challenges of organizing both a Java User Group and an entire conference…

Guests

• Pratik Patel
  • https://twitter.com/prpatel
  • https://www.linkedin.com/in/prpatel/ 
  • Lead Dev Rel at Azul
• Vincent Mayers
  • https://twitter.com/vincentmayers
  • https://www.linkedin.com/in/vincentmayers/ 
  • Dev Community at Gradle

Podcast host

• Frank Delporte (@[email protected], @frankdelporte)

Links

• Atlanta JUG
  • https://ajug.org/
  • https://twitter.com/atlantajug
• DevNexus
  • 4-6th of April 2023, Atlanta US
  • https://devnexus.org/

Content

• 00’00 Intro
•  00’36 Introduction of the guests
•  01’37 How the Atlanta JUG started
  •  NYJavaSIG: https://www.javasig.com/
• 03’17 Why the guests joined the Atlanta JUG and became organizers
•  04’39 Impact of Covid
•  05’39 Venue is a hotel or co-working space
•  06’34 Atlanta JUG is a US non-profit
  • https://sessionize.com/s/vincentmayers/the-jug-business-tips-n-tricks-for-running-an-amaz/51617
•  10’22 Other people involved in the organization
•  12’27 Number of JUG visitors
•  14’04 Most remarkable sessions
•  16’35 Starting a JUG is “just do it”, a formal structure is not a requirement, and how to find speakers
  •  https://jugs.groups.io/g/jug-leaders
• 20’53 About DevNexus, how it started, the many tracks,…
  • https://devnexus.com/presentations/beyond-rest-and-crud-integration-patterns-in-microservices
  • https://devnexus.com/presentations/patterns-predictions-and-prescriptions 
  • https://foojay.io/today/visualizing-brain-computer-interface-data-using-javafx/ 
  • https://devnexus.org/presentations/observing-minecraft 
•  42’17 Who is visiting DevNexus and Atlanta JUG
•  52’16 Outro

TornadoVM is a programming and execution framework for offloading and running JVM applications on multi-core CPUs, GPUs, and FPGAs. With the same code, some of your existing program code can be executed hundreds of times faster!

Guests

• Juan Fumero, TornadoVM Lead Architect
  • https://twitter.com/snatverk
• Christos Kotselidis, TornadoVM Project Leader
  • https://twitter.com/CKotselidis
• Thanos Stratikopoulos, TornadoVM Senior Solutions Architect
  • https://twitter.com/thanos_str
• Jakob Jenkov
  • https://twitter.com/jjenkov 

Podcast 

• Host: Erik Costlow
  • https://twitter.com/costlow
• Production: Frank Delporte 
  • https://twitter.com/FrankDelporte

Content

• 00’00 Intro
• 00’36 Introduction of the guests
• 04’26 What is TornadoVM?
  • https://foojay.io/today/hardware-acceleration-for-java-tornadovm-can-do-it/
  • https://fosdem.org/2023/schedule/event/hardware/
  • https://www.tornadovm.org/
• 05’54 How applications can make use of the acceleration provided by TornadoVM
• 11’48 The difference between CPU threads and GPU instruction chain
• 13’42 Possible use cases for TornadoVM
• 15’23 Results on Apple M1
  • https://foojay.io/today/a-flavour-of-tornadovm-on-apple-m1-pro/
• 17’19 Can TornadoVM be used in cloud environments
• 21’18 How to use the API
  • https://foojay.io/today/migrating-applications-to-tornadovm-v0-15-part-1/
  • https://foojay.io/today/migrating-applications-to-tornadovm-v0-15-part-2/ 
• 24’41 Jakobs view of what would be a good match between TornadoVM and cloud usage on AWS Lambdas
  • https://foojay.io/today/azul-provides-the-crac-in-aws-snapstart-builds/
  • https://foojay.io/today/how-to-run-a-java-application-with-crac-in-a-docker-container/
  • AWS GPU and CPU capabilities: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-gpu.html 
• 30’54 The complexity of GPU and FPGA programming languages and handling the differences between different architectures of GPUs, CPUs, and FPGAs
  • https://www.khronos.org/ 
• 40’28 How TornadoVM could be used to heat up buildings, help to reduce the total cloud cost for companies, and run ChatGPT
• 43’30 Relationship between project Panama and TornadoVM
• 48’10 How to get started with TornadoVM
  • https://tornadovm.readthedocs.io/en/latest/introduction.html
• 54’41 Outro

Since 2018, we get a new version of Java every 6 months. Some are long-term supported versions that can be used for many years, while others are only maintained for a short time. Version 20 is such a short-term supported version. So, what new features does this version bring? And why should we use it? And what can we expect from the next version, 21, in September that will be a long-term supported version? Let's find out and learn more about the process of the OpenJDK evolution!

Guests

• Simon Ritter
  • https://twitter.com/speakjava
  • https://mastodon.social/@speakjava 
  • https://www.linkedin.com/in/siritter/
• Miro Wengner
  • https://twitter.com/miragemiko
  • https://www.linkedin.com/in/mwengner/
  • https://www.amazon.de/dp/180461467X

Podcast host

• Frank Delporte
  • https://twitter.com/FrankDelporte
  • https://foojay.social/@frankdelporte

Content

• 00’00 Intro
• 00’40 Introduction of the guests
• 02’03 What new features does Java 20 bring?
  • https://foojay.io/today/what-the-heck-is-project-loom-for-java/
  • https://foojay.io/today/an-introduction-to-scoped-values-in-java/ 
• 03’46 What are preview and incubator features
• 07’16 Other changes in Java 20 and when we can expect them to be “finished”
  • https://foojay.io/today/thinking-about-massive-throughput-meet-virtual-threads/ 
• 10’01 Will all preview and incubator work get into a next version?
• 11’12 How OpenJDK evolves and new features are integrated
  • https://openjdk.org/projects/amber/
  • https://openjdk.org/projects/panama/
  • https://openjdk.org/projects/valhalla/
• 13’25 About Miro’s book
• 15’28 About the module system
• 17’25 References from Miro’s book to the OpenJDK code
  • https://foojay.io/today/book-review-practical-design-patterns-for-java-developers/ 
  • https://foojay.io/today/42-practical-java-design-patterns-builder-and-more/ 
  • https://www.azul.com/blog/time-zone-and-currency-database-in-jdk/
• 20’41 Don’t implement yourself what already exists
• 25’51 The importance of the approach how you program
• 28’26 Thread improvements in Java 20
• 29’24 Why you should use Java 20 as a developer
• 30’22 Java 20 is a full stable release with the same quality as all other releases
• 31’11 How other new features will be included in Java 21
• 32’52 Phases of a release process
• 34’02 Updates in the JEPs related to Java 20
  • https://www.youtube.com/watch?v=OlW724WaJJQ&t=1869s (when when when)
• 39’48 Outro

Last month we were in the US, and this time we travel to the other side of the world as we spoke with the organizers of the Japan JUG!

Guests

•  Shin Tanimoto
  • https://twitter.com/cero_t 
  • https://www.linkedin.com/in/shintanimoto/
• Ayana Yokota 
  • https://twitter.com/ihcomega
  • https://www.linkedin.com/in/ayana-yokota-ihcomega/
• Maaya Ishida 
  • https://twitter.com/maaya8585
  • https://www.linkedin.com/in/maaya-ishida-5486b7109/ 

Podcast host

• Frank Delporte (@[email protected], @frankdelporte)

Links

• JJUG (Japan JUG)
  • Contact: https://jjug.doorkeeper.jp/contact/new 
  • https://twitter.com/JJUG 
  • https://facebook.com/japanjug 
  • JOnsen: https://jonsen.jp
  • JJUG CCC 2023 Spring: https://sessionize.com/jjug-ccc-spring-2023/
• Javajo (Java women user group) 
  • Contact: https://javajo.doorkeeper.jp/contact/new 
  • https://twitter.com/java_women 
  • https://facebook.com/groups/javajo 
  • https://instagram.com/javajo_tokyo/

Content

• 00'00 Intro and music 
• 00’13 About the topic of this podcast 
• 00'58 Introduction of the guests and host
•  02’46 The start of JJUG and Jajavo
  •  https://www.seasar.org
  •  https://www.seasar.org/en/  
  •  https://github.com/seasarorg
•  05’21 Personal reasons to organise a JUG
•  08’14 How many events are organised
•  09’08 Which speakers come to the events
•  09’57 Impact of Covid
•  12’59 The number and mix of attendees at Japanese events
•  14’26 Trends in popular topics
•  16’27 Plans for the future
  •  JOnsen: https://jonsen.jp
•  19’17 Questions for the listeners
•  20’56 Outro