Announcing The New Foojay
Foojay has a new home: a static, open-source site where publishing an article is a pull request. Same URLs, same archive, much faster, and new features.
Frank Delporte
123 viewsfoojay.io - Friends Of OpenJDK
Foojay is the vendor-neutral home for the Java community with daily news, OpenJDK data, podcasts and guides, made by the developers who use it. What is Foojay? →
Most recent post
Frank Delporte
123 views
Welcome to the new Foojay!
The same content from amazing Java developers, now in a new home. Foojay has been rebuilt from the ground up!
Cut Code Review Time & Bugs in Half. Instantly.
Supercharge your team to ship faster with the most advanced AI code reviews.
Get Started!Sponsored Content
Free eBook: Sustainability for Java Developers
Towards an understanding of sustainable software development, written by and for the friends of OpenJDK
Your GPU spend is optimized. Your JVM probably isn’t.
Hidden JVM inefficiencies - GC pauses, conservative JIT, slow warm-up - are quietly draining your AI infrastructure's performance and cloud spend. This guide shows how to eliminate that drag and scale with fewer nodes.
Download NowSponsored Content
Nicolas Frankel
61 viewsWorld geography gotchas
Years ago, a colleague of mine told me about two pockets of foreign land surrounded by Switzerland: Campione d'Italia and Büsingen am …
Cristobal Escobar
122 viewsBoxLang 1.17.0 Released: Module Inception, CLI Checker, Jar Loading and much more!
BoxLang has always been an extensible language. As of 1.17.0, it is a hierarchically extensible one. Modules can now contain other modules; …
Dominika Tasarz
200 viewsWhat's New In The September 2026 Azul Payara Release?
MicroProfile 7.1 lands on the commercial lines, OpenTracing is removed, and Jakarta Agentic AI reaches Payara Micro in the September Azul …
Viktoria Evdokimova
163 viewsCan You Explain the Diff Your AI Agent Just Wrote?
Every Java developer has been in a code review where the question is simple: What does this method do? The answer used to tell you …
Ricardo Mello
185 viewsHow I Built an AI Assistant for My Career with Java, Spring AI, and MongoDB
How one developer built a personal AI assistant in Java using Spring AI, MongoDB Vector Search, conversation memory, and tool calling with …
Hanno Embregts
170 viewsHello Java 27! Have You Been Working Out?
Java 27 is like that friend that you haven't seen all summer, and when you finally see them again it's clear that they spent a lot of time …
199 viewsFoojay Podcast #101: Java 27 in Practice: Smaller Heaps, Smarter Defaults, and Valhalla on the Horizon
JDK 27 arrives on 15 September 2026, and it is a feature release rather than a Long-Term Support one. That distinction matters less than it …
Richard Fichtner
156 viewsCome for Java. Get a Whole Lot More.
JCON USA returns inside IBM TechXchange 2026 with two rooms of deep Java content, a dedicated community home, and direct access to one of …
Dmitry Moskalyuk
254 viewsReflection-Free Serialization on the JVM: Four Formats In, Avro Out
I run a model layer that accepts the same business data in JSON, XML, YAML, and TOML and converts it all to Avro. The project was …
Viktoria Evdokimova
156 viewsOne Base URL, Many Coding Agents: What an OpenAI-Compatible Gateway Looks Like From java.net.http
Somewhere in every coding agent there is an HTTP client. Claude Code, Codex, Cursor, Cline, OpenCode: strip away the terminal UI or the …
Podcasts
Catch up on the most recent episodes and stay updated with the latest OpenJDK innovations.
199 viewsFoojay Podcast #101: Java 27 in Practice: Smaller Heaps, Smarter Defaults, and Valhalla on the Horizon
JDK 27 arrives on 15 September 2026, and it is a feature release rather than a Long-Term Support one. That distinction matters less than it …
593 viewsFoojay Podcast #100: Java Podcasters on Why They Started, What Broke, and What They Learned
Foojay Podcast hits episode 100. No plan, no roadmap. It just happened. To mark the occasion, Frank turned the microphone around and invited …
Michal Maléř
621 viewsQuarkus Unpacked: Insights from the Foojay Podcast
I recently had the pleasure of joining the Foojay podcast to talk about Quarkus in depth. The conversation covered a lot of ground, from …
671 viewsFoojay Podcast #99: Testing the Untestable: LLM Security for Java Developers with Tiberius
Your Java AI app is live. But have you tested whether it can be jailbroken? Iryna Dohndorf introduces Tiberius, an open-source security …
Happening in the next two weeks
Meetups from Java User Groups worldwide, plus the conferences and workshops on the calendar.
- 23 Sep Vom Monolithen zum Modulithen: Event-basierte Architektur mit Spring Modulith
- 23 Sep DubJUG 269: Geertjan and Ivan
- 23 Sep Knowns and Unknowns: Testing AI-Generated Code
- 23 Sep Workshop Hands-On: Kiro Express — Desarrollo de Software Impulsado por IA
- 24 Sep From Search to AI: How Retrieval Evolved
- 24 Sep ArnhemJUG - September meetup
- 24 Sep Amsterdam JUG Meetup at Picnic
- 24 Sep Architecture for the Agentic Era and Make Cybersecurity Fun
- 24 Sep Renovate – Dein Freund und Helfer für Dependency Updates
- 24 Sep Vom Monolithen zum Modulithen: Spring Modulith in der Praxis (Nils Hartmann)
- 24 Sep Known and Unknowns: Testing AI Generated Code
- 24 Sep Choose Your Own AI Adventure: Java, agents, and rabbit holes
- 25 Sep Java Stammtisch
- 28 Sep Explyt Webinar: Working with AI Tools at the User Level 2026
- 29 Sep dev connect OWL 2026
- 29 Sep BrabantJUG @ TOPDesk
- 30 Sep Amsterdam JUG OTel Workshop at Dash0
- 30 Sep Maven/Open Source (Sandra Parsick)
- 30 Sep Embabel, an Agentic AI Framework
- 1 Oct October 2026: Snake in 10 Lines and the Identity of AI Agents
- 1 Oct JUG DA: Double Feature: Value Objects and Project Valhalla + Java for AI (Nicolai Parlog, Zoran Sevarac)
- 1 Oct LJC Meetup at Engine by Starling
- 5–9 Oct Devoxx Belgium 2026
- 5 Oct Amsterdam JUG Meetup at Mollie
- 5 Oct A Java 8 lambda and JobRunr is all you need for distributed (batch) processing (Ronald Dehuysser)
- 5 Oct Modernizing Java EE Monoliths: A Roadmap to Scalable Microservices
- 5 Oct LJC Roundtable: The JCP, Java Community & The Future of Java
- 5 Oct Building Intelligent Java Apps: Agent Patterns, MCP, and the Future of AI Native
- 6 Oct Monatlicher Stammtisch der JUG Berlin-Brandenburg
Getting started with Java
Is Java your first language, or are you coming from another one? Let Friends Of OpenJDK help you get up and running.
Install Java
One-time setup to get Java on your machine: check whether you already have it, then install it on Windows, macOS or Linux.
Quick Start Tutorial
A high-speed introduction to Java in single source files: no project, no build tool, just java HelloWorld.java and go.
Done, or want another voice? 6 more free Java courses and tutorials, picked by the community.
Most popular post categories
Explore the full breadth of what the community writes about.