Posts on webtechie.be

First Test of Java on Banana Pi (ARM and RISC-V), Plus a Blinking LED with Pi4J

Thu, 16 Jul 2026 00:00:00 +0000

As part of my 2026 learning goals around Java on RISC-V (see this post about x86 versus ARM versus RISC-V ), I’ve asked various suppliers to send me evaluation boards. I already published these:

A New Website for MelodyMatrix, and What's New in Release 1.1.0

Mon, 13 Jul 2026 00:00:00 +0000

Last week was busy for MelodyMatrix . The website got rebuilt from the ground up, and the app itself got a solid release with a handful of new features.

My Book 'Java Programming for Raspberry Pi' is Now Available as Softcover and Hardcover on Amazon

Fri, 10 Jul 2026 00:00:00 +0000

“Java Programming for Raspberry Pi: A Hands-On Guide to Electronics and IoT Projects” is now available as a softcover and hardcover paper book through Amazon, on top of the Kindle ebook and the pay-as-you-wish version on Leanpub . If you prefer holding a physical book while you’re wiring up LEDs and sensors on your Raspberry Pi, that’s now possible again.

Closing the Visual Gap Between the Official Lottie Webplayer and Lottie4J

Thu, 02 Jul 2026 00:00:00 +0000

A Lottie library is only as good as its output looks. If an animation renders differently in Lottie4J than it does in the official web player, that’s a bug, even when no exception is thrown and the code looks correct.

JavaFX Links of June 2026

Fri, 26 Jun 2026 00:00:00 +0000

Here are the JavaFX LinksOfTheMonth of June 2026. You can find the weekly lists on jfx-central.com . Did we miss anything? Is there anything you want to have included in one of the next overviews? Let us know via links@jfx-central.com .

From breadboard chaos to a real PCB: designing the Pi4J smoke test board

Thu, 25 Jun 2026 00:00:00 +0000

Testing a Java I/O library properly means testing it on real hardware. No mocks, no stubs, just actual pins doing actual things. For Pi4J, that means running the smoke test: a setup with two BMP/BME280 sensors, some GPIO-to-GPIO jumper connections, and a bunch of patience while you untangle the wires for the third time this week.

JavaFX In Action #27 with David Gutierrez about JMathAnim to Create Mathematical Animations

Thu, 25 Jun 2026 00:00:00 +0000

The JFX Central Links Of The Week is a great source to discover what is happening in the JavaFX world. One of the projects that caught my eye is JMathAnim, a tool to create mathematical animations built on top of JavaFX. In this interview, David Gutierrez, a mathematician from Spain, walks us through what the project can do and how it came to life.

A Fresh Design for webtechie.be

Wed, 17 Jun 2026 00:00:00 +0000

This website grew over many years into more than 260 posts, 220 videos, 100 podcasts, and 60 presentations. The old design buried most of that under a layout that no longer matched the way I write today. So I rebuilt it from the ground up, and the result puts the content first.

Lottie4J Meets LottieFiles: A Conversation with Naail Abdul Rahman

Thu, 04 Jun 2026 00:00:00 +0000

Lottie animations run on Android, iOS, and the web. Getting them working on the JVM is a different story. Lottie4J started as a question: can JavaFX render them without a WebView? That question turned into a library with a first release in March 2026! Since then, I received the first pull requests, recently added headless unit testing with JavaFX 26, and now this: a video conversation with Naail from the LottieFiles team.

JavaFX Links of May 2026

Fri, 29 May 2026 00:00:00 +0000

Here are the JavaFX LinksOfTheMonth of May 2026. You can find the weekly lists on jfx-central.com . Did we miss anything? Is there anything you want to have included in one of the next overviews? Let us know via links@jfx-central.com .

JavaFX Links of April 2026

Fri, 24 Apr 2026 00:00:00 +0000

Here are the JavaFX LinksOfTheMonth of April 2026. You can find the weekly lists on jfx-central.com . Did we miss anything? Is there anything you want to have included in one of the next overviews? Let us know via links@jfx-central.com .

Links from the JCON talk 'Foreign Function & Memory (FFM) API on Raspberry Pi'

Wed, 22 Apr 2026 00:00:00 +0000

These are the links from the JCON talk in Cologne, Germany, on April 22, 2026: “The Wait is Over: Foreign Function & Memory (FFM) API brings modern Java to the Raspberry Pi ”.

Debugging BentoFX in MelodyMatrix with Matt Coley, Scenic View, and an Honest Look at AI-Generated Code

Tue, 21 Apr 2026 00:00:00 +0000

There are bugs you can solve by yourself, and bugs where you just need to sit down with someone who knows the internals. This video is in the second category. MelodyMatrix uses BentoFX for its dockable panel layout. Branches, leaves, tabs on the side, content panels that open and close. It works well until something fights the layout. But I had some visual problems I could not explain, some code that felt more complicated than it should be, and no good explanation for why.

Testing Lottie4J JavaFX Animations in GitHub Actions Without a Display: JavaFX 26 Headless to the Rescue

Mon, 20 Apr 2026 00:00:00 +0000

When I released Lottie4J 1.1.0 , I mentioned something a bit embarrassing in the release notes and this blog post : there was a new unit test to compare the JavaFX player output against a JavaScript reference player, but it “can not run on CI, because it requires a display output.” A TODO. A known limitation. One of those notes you write hoping future-you will figure it out.

MelodyMatrix V1.0.0 Released: Shipping a JavaFX App with jDeploy, GitHub Actions, and Auto-Update

Thu, 16 Apr 2026 00:00:00 +0000

Some side projects take a while to get to a proper release. MelodyMatrix is one of those. The app has been downloadable for quite some time thanks to jDeploy , but there was no official V1.0.0 yet. No tagged release. No moment of “okay, this is it.” Just a rolling build on every commit to the main branch.

Validating Pi4J V4 on real hardware, catching bugs, and exploring the Ikalogic logic analyser

Mon, 30 Mar 2026 00:00:00 +0000

Pi4J contributor Tom Aarts joins Frank Delporte for a hands-on session focused on hardware testing in Pi4J V4. Tom has been a long-time contributor to the Pi4J ecosystem. He added example devices, improved core code by finding gaps through real-world usage, and most recently designed the Pi4J Smoke Test hardware setup that makes integration testing on real Raspberry Pi hardware practical and repeatable.

JavaFX Links of March 2026

Fri, 27 Mar 2026 00:00:00 +0000

Here are the JavaFX LinksOfTheMonth of March 2026. You can find the weekly lists on jfx-central.com . Did we miss anything? Is there anything you want to have included in one of the next overviews? Let us know via links@jfx-central.com .

Lottie4J 1.2.0: dotLottie Support, Marker Playback, Cropping, and a Big Speed Boost

Fri, 20 Mar 2026 00:00:00 +0000

Version 1.2.0 of Lottie4J is out, and it’s again a big release! The headline feature is support for the .lottie container format, but that’s just the start. This release also brings marker-based playback, cropping, adaptive rendering, significant performance improvements, and a lot of core model fixes driven by testing more complex real-world animations.

Let's smoke some food with Pi4J, Vaadin, and Quarkus

Thu, 19 Mar 2026 00:00:00 +0000

Live stream with Matti Tahvonen and Frank Delporte with the smell of smoked food and fresh Java code! Matti from the Vaadin team shows a project that started as a Raspberry Pi side project and turned into a full-blown IoT application. He has built a smoker controller — yes, an actual BBQ smoker — with Pi4J V4, Vaadin for the UI, and Quarkus on the backend. So we can now officially say that Pi4J V4 has been smoke-tested in production…

Lottie4J 1.1.0: Better Rendering, Smarter Debugging, and an animated Lottie4J Logo!

Tue, 10 Mar 2026 00:00:00 +0000

Just one week after the first public release of Lottie4J , the open-source Java library for rendering Lottie animations in JavaFX, version 1.1.0 is already out. And it’s a big one!