Building openjfx

[Orion Poplawski]

So I'm stepping back to simply try building openjfx with gradlew but I get:

$ sh gradlew --info build
Initialized native services in: /home/orion/.gradle/native
Initialized jansi services in: /home/orion/.gradle/native
The client will now receive all logging from the daemon (pid: 253483). 
The daemon log file: /home/orion/.gradle/daemon/8.14.2/daemon-253483.out.log
Starting 2nd build in daemon [uptime: 2 mins 22.763 secs, performance: 
97%, GC rate: 0.00/s, heap usage: 2% of 512 MiB, non-heap usage: 9% of 
384 MiB]
Using 6 worker leases.
Now considering [/home/orion/openjfx-25/jfx25u-25-29] as hierarchies to 
watch
Now considering [/home/orion/openjfx-25/jfx25u-25-29/buildSrc, 
/home/orion/openjfx-25/jfx25u-25-29] as hierarchies to watch
Watching the file system is configured to be enabled if available
File system watching is active
Starting Build
Caching disabled for Groovy DSL script compilation (settings) because:
   Build cache is disabled
   Not worth caching.
Compiling settings file 
'/home/orion/openjfx-25/jfx25u-25-29/settings.gradle' using 
BuildScriptTransformer.

FAILURE: Build failed with an exception.

* What went wrong:
BUG! exception in phase 'semantic analysis' in source unit 
'_BuildScript_' Unsupported class file major version 69
 > Unsupported class file major version 69

* Try:
 > Run with --stacktrace option to get the stack trace.
 > Run with --debug option to get more log output.
 > Run with --scan to get full insights.
 > Get more help at https://help.gradle.org.

BUILD FAILED in 466ms

$ java --version
openjdk 25 2025-09-16
OpenJDK Runtime Environment (Red_Hat-25.0.0.0.36-1) (build 25+36)
OpenJDK 64-Bit Server VM (Red_Hat-25.0.0.0.36-1) (build 25+36, mixed 
mode, sharing)

What am I doing wrong?

-- 
Orion Poplawski
he/him/his  - surely the least important thing about me
IT Systems Manager                         720-772-5637
NWRA, Boulder/CoRA Office             FAX: 303-415-9702
3380 Mitchell Lane                       orion at nwra.com
Boulder, CO 80301                 https://www.nwra.com/