Java Concurrency

Join in with the latest Amsterdam JUG Meetup with the [GIGABITES Community](https://www.meetup.com/gigabites-just-eat-takeaway-com) at **Just Eat Takeaway.com (JET)**, at [Piet Heinkade 61, 1019 GM, Amsterdam](https://maps.app.goo.gl/a8vmLkhP7taSwPXH8). **Agenda** **18:00 -** Doors Open (And Food!), thanks JET! **18:30 - 19:30** Talk 1: **The JET** **Journey with Apache Flink -** [Behrooz Mirzaie](https://www.linkedin.com/in/behrooz-mirzaie/) (Tech Lead at JET) **19:30 - 19:45 Short Break** **19:45 - 20:45** Talk 2: **From Tables to Streams: Apache Flink for SQL Developers -** [Viktor Gamov](https://www.linkedin.com/in/vikgamov/) (Principal Developer Advocate at Confluent) **21:00 The End** **Abstracts** **Talk 1: The JET Journey with Apache Flink -** [Behrooz Mirzaie](https://www.linkedin.com/in/behrooz-mirzaie/) Our journey with Apache Flink at JET begins with the recognition that while Flink is powerful and that our primary job is to make that power approachable for everyone. This realization led us to consider "What If? Abstracting complexities" as part of our diagnosis. In this sesion, we will discuss how, ultimately, the core lesson we've learned is to hide the complexity, though not the capability, of the underlying system! **Talk 2: From Tables to Streams: Apache Flink for SQL Developers -** [Viktor Gamov](https://www.linkedin.com/in/vikgamov/) (Confluent) What if your SQL queries could process data as it happens instead of after it's stored? Apache Flink speaks SQL fluently, but it's not a database – think of it as a conductor orchestrating endless streams of data rather than a librarian managing stored records. This session bridges the gap between traditional SQL and stream processing. We'll explore: * The Mental Model Shift – From "query the database" to "continuously process the stream" using intuitive analogies * Flink SQL in Action: How familiar operations like SELECT, JOIN, and GROUP BY work on infinite data streams, plus temporal joins, time windows, and watermarks * Table API: Programmatic control with declarative simplicity, bridging SQL and complete programming flexibility * Flink AI: Real-time feature engineering and model inference on streaming data using SQL-like patterns * Real-World Patterns: Fraud detection during transactions, live analytics dashboards, and event-driven architectures You'll leave understanding not just how to use Flink SQL, but when and why it transforms traditional database skills into real-time data superpowers. Perfect for: SQL developers and data engineers ready to make their queries travel through time.

**3D Workshop** * **Ontwerpen met Fusion360** * **Scannen in 3D** * **Het gebruik van 3D printers** **Je bent nu welkom in de nieuwe locatie NewTechPark** Je kunt ook online aan deze fysieke bijeenkomst deelnemen. De bijeenkomst is dan op de locatie te volgen. Als je [hier](w.j.put@hccnet.nl) vooraf een mailtje stuurt kun je dinsdagavond tussen 19.00 en 20.00 uur inloggen met Jitsi voor vragen, of ter kennismaking met hcc!3D. Online neem je deel aan de bijeenkomst met [https://wij.hcc.nl/3D](https://wij.hcc.nl/3D) [(Alleen toegang als je zichtbaar bent met voor- en achternaam. )](https://wij.hcc.nl/3d)

Join us on **June 2 at 5:00 PM** at **the Postillion Hotel Bar** for an evening of great food, relaxed conversations, and plenty of deep dives into all things **Identity & Access Management**, **Customer IAM**, and **Digital Identities**. This is the perfect way to finalize the Heliview IAM experience together with your fellow IAM enthusiasts. If you work with identity, security, authentication, authorization, or related tech, you’ll feel right at home. Come along, grab a drink, meet fellow practitioners, and be part of the ongoing conversation shaping the future of digital identity. Looking forward to seeing you there! More info on the conference: [Identity & Access Management](https://heliview.com/identity-access-management/)

Every Tuesday, the group 024 Waalrunners go for a run at a distance of between 7km - 10km depending on the group. Everyone is welcome to join, you just need to turn up at 20:00 on Tuesday in front of Brouwerij De Hemel. There are different routes every time, and the group welcome all new people to join them. [https://www.facebook.com/024waalrunners-710731759317504](https://www.facebook.com/024waalrunners-710731759317504)

Is public speaking something you’ve always wanted to learn? Then you’ve come to the right place! Experience a safe and playful environment at U-Speak Toastmasters where you can develop your public speaking, communication, and leadership skills! ## **Welcome to U-Speak! Toastmasters** Join our vibrant community at U-Speak!, where internationals and Dutch locals from Utrecht and its surroundings come together. U-speak! Toastmasters is a welcoming, safe, supportive and playful environment where you can work on your public speaking, communication and leadership skills! ## **Discover our meeting experience** Curious about what happens during our meetings? Here’s a glimpse into a typical evening at U-Speak! Our gatherings feature a lineup of three prepared speeches, engaging evaluations and impromptu speaking sessions. At U-Speak!, every member gets their chance to shine. Whether you’re delivering a speech, providing feedback, or stepping up for impromptu speaking, our supportive environment ensures that everyone’s voice is heard and valued. * ⏰ Time: 19:15 - 21:30 (7.15pm to 9.30pm) Walkin at 19:15; Start of the meeting at 19:30 * 🌐 Venue: Room 8, Top Floor, Pub Florin, Utrecht * 🙋🙋‍♂️🙋‍♀️Attendance: Typically, 15-20 people attend each meeting Many of our club members are not on Meetup, so the number of people attending as indicated here is not reflective of the actual number of people attending on a night. * 🙋🙋‍♂️🙋‍♀️ Guests are welcome; rsvp is encouraged

Join us for an evening of good vibes! Whether you’re a local or an expat, Mingle Mania is the perfect place to socialize and make friends or even to practice languages. 🤝🤼‍♂️💬🙋‍♂️🫂 👉 Join [https://chat.whatsapp.com/GopSuzuFKRBKeYVKQrX4pE](https://chat.whatsapp.com/GopSuzuFKRBKeYVKQrX4pE) The group has many regular members, we intend to do various type of events, the goal is to build a strong community for all sorts of activities. If you have an event idea that you would like to see happen, let us know. We generally have about 20 participants, the age is between 20 and 60 averaging somewhere around 30, language exchange is not strictly enforced, culture exchange happens naturally. **mingle** (verb, intransitive): to move among people and talk to them, especially at a social event. 📍 **What We Are:** * A diverse group of locals and expats * ...going out at least every Tuesday 😊 🆓 **Event Details:** * It is free to join and operated on a voluntary basis! * Please honor the bar by ordering at least one drink.

Hi Everyone, This is our weekly open hackerspace evening! Usually from 19:00 :-) Feel free to drop by, come and nerd with us! See this Tuesday! We're in room 126, ring the room number and we'll open the door. We're located on the first floor

We are excited to announce our next Utrecht JUG meetup on **June 3rd** hosted by **Keylane**. Join us for an evening full of creativity, innovation, and practical insights from the Java and Spring ecosystem. As always, you can expect inspiring talks, great conversations, food, drinks, and plenty of opportunities to connect with fellow developers. We start the evening with food and drinks before diving into our first session, where **Alexander Chatzizacharias** takes Spring Boot far beyond its intended use case. In a talk that combines humor, curiosity, and technical depth, Alexander explores what happens when you use Spring Boot as the foundation for real-time game development. From IoC containers to event listeners, this session offers a fresh and entertaining perspective on the Spring ecosystem and the joy of learning by experimentation. After the break, **Josh Long** and **James Ward** take the stage with Bootiful Spring AI. Artificial Intelligence is rapidly becoming part of modern software development, and this session explores how Spring AI makes integrating AI capabilities into Java applications approachable and powerful. Expect an engaging introduction to modern AI concepts and a practical look at how the Spring ecosystem embraces the next wave of AI engineering. Please join us and RSVP! Because of the limited number of seats, please keep your RSVP up-to-date, so we can welcome someone else if you can't make it. **Timeschedule** 17:00 Doors open 18:00 Food & Drinks 18:45 Let's use Spring Boot to build games, because why not? by Alexander Chatzizacharias 19:45 Break 20:00 Bootiful Spring AI by Josh Long & James Ward 21:00 Drinks **Giveaway** 1 JetBrains licence **Talks** **Let's use Spring Boot to build games, because why not?** If you work on enterprise grade microservices on the JVM, you have undoubtedly heard of Spring Boot. Most developers see it as the reliable backbone of enterprise software. It is stable, predictable, and safe. But what if we took all those conventions and threw them out the window? What if we repurposed the IoC container, event listeners, and bean lifecycles to reveal what Spring Boot was always meant to be? A game development framework! Join Alexander as he attempts to deconstruct and demystify the Spring ecosystem by forcing it to do things it was definitely not designed for. We are not talking about simple text adventures here. We are talking about building complex, real-time games like a Terraria clone or a souls-like RPG, all powered by the same annotations you use for your day job. This session explores what happens when you learn technologies by breaking them. Whether you are a Spring veteran or a newcomer, this talk offers a fresh perspective on the tools you use every day. You will leave with a better understanding of how Spring Boot works under the hood and the inspiration to build something completely unnecessary, just because you can. Come for the absurdity, stay for the laughs, and see what happens when you strip away conventions and best practices in the pursuit of a wild idea. **Bootiful Spring AI** The age of artificial intelligence (because the search for regular intelligence hasn't gone well..) is nearly at hand, and it's everywhere! But is it in your application? It should be. AI is about integration, and here the Java and Spring communities come second to nobody. In this talk, we'll demystify the concepts of modern day Artificial Intelligence and look at its integration with the white hot new Spring AI project, a framework that builds on the richness of Spring Boot to extend them to the wide world of AI engineering. **Speakers** **Alexander Chatzizacharias** Alexander, a 35-year-old Software Engineer at JDriven, holds dual Dutch and Greek nationality. He earned his master’s degree in Game Studies from the University of Amsterdam, where he discovered his passion for gamification and software engineering. Alexander aims to bridge the gap between game development and software engineering, believing that both industries have much to learn from each other. He is dedicated to integrating technologies and methodologies from both fields. Additionally, he enjoys experimenting with new technologies and cutting-edge SDKs. **Josh Long** Josh (@starbuxman) has been the first Spring Developer Advocate since 2010. Josh is a Java Champion, author of seven books (including Reactive Spring), creator of numerous video trainings, open-source contributor, YouTuber, and podcaster. He is a well-known voice in the Spring community and a passionate advocate for Java developers around the world. **James Ward** Professional software developer since 1997, with much of that time spent helping developers build software that doesn't suck. A typed pure functional programming zealot who often compromises on his ideals to just get stuff done. Currently a Developer Advocate for AWS.

Dear JUG members, We’re happy to share that ApeldoornJUG will once again serve as an official Community Ambassador for **J-Spring 2026 – The Future of Modern Java**. 📍 J-Spring Conference 2026 🗓 June 4, 2026 📌 Kinepolis Utrecht **This year’s conference will cover:** • Data, AI, GenAI & prompt engineering • Platform engineering & architecture • Security • People & Culture • New & exciting topics Featuring speakers such as **Holly Cummins, Josh Long, Marit van Dijk, Nicolai Parlog, and many more.** Expect inspiring keynotes, hands-on workshops, and labs. Also returning this year: **The Mentorship Hub powered by Bruno Souza**. **The talk schedule is now live:** 👉 [www.jspring.nl](https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.jspring.nl%2F&data=05%7C02%7Ca_de_ruiter%40belastingdienst.nl%7C757f3b88ba6a4ee59d8e08dea6c04f2b%7Cc8fba4776d4d4f00941a6e6150c721f3%7C0%7C0%7C639131542095649438%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=cPr6C5RZu19Vm4tM%2FXDakYUCx5qf1sztXzyHIqvUGgY%3D&reserved=0) Looking forward to seeing you there!

**Keeping control of your polyglot codebase**, while it grows and ages, can become increasingly difficult. And, using generative AI only makes it more difficult to keep in control. Off-the-shelf linting / QA tools offer great deterministic guardrails to enforce conventions in your code base, but typically don’t offer a simple way to extend them with custom rules. Also, performing searches on a codebase tends to be error-prone due to having to rely on regex, unexpected formatting differences, or the existence of comments. Moreover, migrating code often involves more than just a search & replace on your codebase, usually takes too long to do manually, or will simply burn too many tokens using LLM agent solutions like Clause Code or Codex. Luckily, nowadays there are tools like ast-grep that act like a Swiss Army knife for your code. They offer a DIY (Do It Yourself) solution for linting (including autofix), structural search, and automated code migrations / rewrites (codemods). Being polyglot, they support many languages such as JavaScript, Java, Kotlin, Python, Bash, YAML, JSON, TypeScript, HTML, and CSS. And, deterministic ast-grep linting could be used as a guardrails to keep your LLM agents in control, while ast-grep search & replace can significantly help reduce LLM token usage when performing large scale refactoring. During the workshop, after a short presentation, **you will get hands-on with ast-grep**. At your own pace, through various exercises, you will learn enough to start using ast-grep proficiently in your day-to-day work.

'HOMEGOING' by Yaa Gyasi 'Two sisters with two very different destinies. One sold into slavery; one a slave trader's wife. The consequences of their fate reverberate through the generations that follow. Taking us from the Gold Coast of Africa to the cotton-picking plantations of Mississippi; from the missionary schools of Ghana to the dive bars of Harlem, spanning three continents and seven generations, Yaa Gyasi has written a miraculous novel - the intimate, gripping story of a brilliantly vivid cast of characters and through their lives the very story of America itself. Epic in its canvas and intimate in its portraits, Homegoing is a searing and profound debut from a masterly new writer.' ***Please read the book and join us for a lively discussion (in English) about the contents during our afternoon book club meeting.*** \-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\- **PLEASE NOTE:** This is an IN-PERSON event in Amersfoort, The Netherlands. Please cancel your attendance in advance if you are unable to join, so that those on the waitlist can participate. Looking forward to seeing you all IN REAL LIFE then! Best regards, Sandra

Iedereen is welkom op onze open Freedom Friday Bitcoin Turnhout Meetup @ het super gezellige café Sint Pieter - Grote Markt 60, 2300 Turnhout Geen presentaties. Geen workshops. Gewoon 1 onderwerp: bitcoin. **Connect with Like-Minded Minds** Engage with the Bitcoin community and mingle with fellow enthusiasts. This meetup is your chance to discuss the future, share ideas, and network with pioneers in the decentralized money world. 🏢 **Central Location**: café Sint Pieter ligt perfect centraal, een ruim cafe op de grote markt van Turnhout. Mark your calendars and spread the word!

\# This meetup is around a third\-party organizer\, Focus Filmtheater\. You can either purchase your ticket online or right before the session\. **Seats are numbered**. # **Title**: Treat Her Like a Lady **Language**: Dutch **Subtitles**: English **Length**: 110 min **Director**: Paloma Aguilera Valdebenito **More info**: https://www.focusarnhem.nl/agenda/english-subs-treat-her-like-a-lady/ **Ticket link**: https://www.focusarnhem.nl/tickets/144301/ **Synopsis:** When single mother Sandra (radiant performance from Nienke Plas) is evicted from her apartment due to fraud, she convinces her daughters that their emergency shelter is a holiday hotel. Sandra is just about keeping it together. Living with her two daughters and partner in a modest but colourful Amsterdam apartment, she makes ends (mostly) meet through cleaning jobs and welfare payments. But when she’s faced with a rapidly mounting series of hurdles – unpaid bills, an accusation of fraud, the revelation that her partner has been cheating – Sandra must draw upon all her determination and creativity to keep her daughters out of social care. An effervescent second feature from Dutch filmmaker and writer Paloma Aguilera Valdebenito (Out of Love, IFFR 2016), this jewel of a film offers poignant criticism of a broken social system with all the vibrancy and optimism of a musical. Nienke Plas is masterful in her central performance as the matriarch, whose fortitude, boldness and charisma bring to mind the best of Almodóvar’s heroines. Featuring a gorgeously saturated colour palette and a fabulous needle-drop soundtrack, Treat Her Like a Lady demonstrates how warmth and resilience can transform the most desperate situations into fresh opportunities for laughter and light. **How it works**: I will be at Focus around 18:30, where we can meet before the movie starts. You can message me to find us. Screening starts at 19:00. After the movie, we can have a drink together. Hope to see you soon!

Want to be a speaker? submit your talk to our Call for Presenters!!! https://sessionize.com/azure-cbus-2026/

WQC has weekly Thursday night social nights at the Westerville Java Central. Come and grab a coffee and connect with the community: low stakes, chill environment, and tasty drinks. No registration is required; come as you are.

Topic to be announced. **THANK YOU** *Franklin University* for hosting our meetup! To learn more about *Franklin University*, please visit their website: https://www.franklin.edu/ **DIRECTIONS** Franklin University Fisher Hall 300 E. Main St, Columbus, OH 43215 Map: https://maps.app.goo.gl/jxjBA2hUmS5qrvhq8 Parking is FREE! Please park in Lot C in front of Fisher Hall. See attached map. NOTE: Map the address only. When mapping with Google Maps it may use the Fisher Hall at OSU, which is NOT correct. **Want to sponsor the pizza and/or bar tab?** Please contact me if you would like to sponsor this meetup's pizza and/or bar tab: angelo@mandato.com

Feeling down? Sometimes depressed? Can't focus? Negativity & stress? Recent losses? Creativity in career and personal life hindered by mental blocks? Sometimes we never fully recover from traumatic experiences. Whether it was yesterday, last week or a year ago, traumatic experiences - a loss of a loved one, losing a job, a breakup - can leave you scarred. You talk about it and feel a little better, but it never goes away. After you hang up the phone, it's still there; the sadness, the cloud, the over-thinking, the worry, the guilt. You try to focus, but you're blocked. You try to look forward into new experiences, new relationships but a cloud is hanging over you, casting a shadow on what you once considered a bright, cheerful future. What happened to your courage? Your strength of character? You're 'why not' attitude? Whoever said 'time heals' must have had a special time machine, because after weeks, months, years, you're wondering - when exactly does that kick in? Sometimes it seems like drinking or drugs are the way to go. But they wear off, and now the problem is still there with added side effects from the drugs. At this free local Meetup event we will talk about: * What causes grief, anxiety and depression to become chronic. * Is it possible to regain your joy and happiness even after traumatic experiences? * How to break away from negativity and focus on the future * What are the steps to take to get control of your mind and your emotions? Learn about a safe, gentle, do-it-yourself counseling that can be done in the comfort of your own home. Let's explore safe, effective solutions for healing from traumatic experiences. Be sure to click on the red "Attend" button below to come to the event. We look forward to seeing you there. This group is sponsored by the Dianetics & Scientology Life Improvement Center.

**✨ Jacksonville Virtual Speed Dating — Hosted on Zoom** Speed dating from your living room. Short Zoom rounds with Jacksonville singles matched to you by age and personality. **Pick your age group and register:** - **Ages 18-32** → [REGISTER HERE](https://tempodating.com/product?productId=531.0&productType=onlineSpeedDating&city=Jacksonville&groupurlname=find-authentic-connections-through-group-outings&ar=18-32&face_v=2.0) - **Ages 30-46** → [REGISTER HERE](https://tempodating.com/product?productId=531.0&productType=onlineSpeedDating&city=Jacksonville&groupurlname=find-authentic-connections-through-group-outings&ar=30-46&face_v=2.0) - **Ages 40-58** → [REGISTER HERE](https://tempodating.com/product?productId=531.0&productType=onlineSpeedDating&city=Jacksonville&groupurlname=find-authentic-connections-through-group-outings&ar=40-58&face_v=2.0) - **Ages 55+** → [REGISTER HERE](https://tempodating.com/product?productId=531.0&productType=onlineSpeedDating&city=Jacksonville&groupurlname=find-authentic-connections-through-group-outings&ar=55+&face_v=2.0) **⚠️ RSVP alone won't secure your spot.** Register through your age group link below and complete the personality quiz. Places are limited. --- **How It Works** 1. **Register** – Pick your age group above and sign up. 2. **Take the quiz** – Short personality quiz so we can match you well. 3. **Join on Zoom** – Your host will guide you through every round. 4. **Get matches** – Mutual matches sent after the event. --- ✨ Sign up, take the quiz, and meet Jacksonville singles tonight. 💘 ✨

Join the CONNECTED Westerville Mastermind Group for a dynamic afternoon of B2B networking! This event is perfect for professionals looking to expand their business connections, share insights, and foster collaboration within the community. Whether you are a seasoned entrepreneur or just starting out, this event offers a valuable opportunity to exchange ideas, build relationships, and grow your network in a supportive environment. Connect with like-minded individuals, explore potential partnerships, and discover new opportunities for professional growth. Don't miss out on this chance to enhance your business network and take your career to the next level with CONNECTED Westerville Mastermind Group! We meet the 4th Monday of every month from 11am-1pm. Welcome and general networking from 11am - 11:30am with core meeting 11;30 - 12:30 and a final round of networking from 12:30 - 1pm.

**Latest Dojo Location!** **Knotty Pine Brewing** 1765 W 3rd Ave, Columbus, OH 43212 We're going to try a new dojo location for a few weeks and see how it works Dojos are informal Python group study sessions where everyone interested in Python gathers to learn about Python, help others with Python, or just hang out. Everyone is welcome from Python beginners to experts. Bringing a laptop is encouraged (we'll have extension cords and power strips). If there's something you want to learn leave a comment on this invite so we can plan ahead. We're looking for speakers for our Monthly Meetups! Fill out the form if you are interested in presenting to the Python Community. https://forms.gle/ehSfUAC2WgR34Crq9