As described before on Java 21+ Not Working on Raspberry Pi Zero 2, a problem appeared to execute Java code on the Raspberry Pi Zero 2 with OpenJDK 21 or higher. Reason: in OpenJDK 21 the Just-In-Time (JIT) compiler has been improved, but this change doesn’t work correctly on the ARM Cortex-A53 processor as used in the Zero 2. It’s another type of processor compared to, for instance, the Raspberry Pi 4 (Cortex-A72) and 5 (Cortex-A76).
These are the links from the Devoxx talk in Antwerp, Belgium, on October 9, 2025: “The Wait is Over: Foreign Function & Memory (FFM) API brings modern Java to the Raspberry Pi”.
Originally posted on the Pi4J website.
Dieter Holz was experimenting with Pi4J V3 on a Raspberry Pi Zero 2. Because this version requires Java 21 or newer, he upgraded his OS to a newer Java version and found out that no Java code could be executed. He tried with Java 21 and 24, and neither worked correctly, although Java 17 runs without problems.
In August, our family vacation brought us to Kazakhstan. An important trip, as it is the birth country of our (now) 14y son. It was over 13 years that we had been there and we planned to go back earlier, but some stupid virus messed up everyones life a few years ago… So finally, early this year, we decided to start organizing our trip. Or to be fully honest, we asked Ardjan of “Kazachstan Reizen” to do that for us. And we had an amazing trip, visited different cities and national parks, and had a fantastic time.