Versions 3.0.0 is based on 2.8.0 (released in January 2025), but bumps the Java version to 21 or newer! We asked our users which minimal Java version we should use, but there was no one clear answer, as expected ;-)
The current/latest Long Term Support (LTS) version of Java is version 21. So it makes sense to jump forward from 11 to 21. This will also prepare us for a the next LTS, which will be Java 25 in September 2025. Bumping to the latest LTS makes it possible to make use of many newer Java language and runtime improvements, simplify some of the code, etc.
We would like to move to Java 22 as this would allow us to easier call C code to interact with the GPIOs, thanks to JEP 454: Foreign Function & Memory API. Unfortanelty, 22 is not a LTS, so it would force us to bump the version every six months with each new release, up till 25.
The sources of V3 can be found in the GitHub repository pi4j/pi4j.
Pi4J version 3.0.0 is a continuation of 2.8.0, but bumps the minimal Java version to 21.
The Pi4J V3 source code is available in this GitHub repository: pi4j/pi4j GitHub Repository
git clone https://github.com/Pi4J/pi4j
Pi4J V3 is not yet released, but you can already use version 3.0.0-SNAPSHOT for testing if you add the snapshot Maven repository to your pom-file.
<repositories>
<repository>
<id>oss-snapshots-repo</id>
<name>Sonatype OSS Maven Repository</name>
<url>https://oss.sonatype.org/content/groups/public</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>