"languageVersion is final and cannot be changed" when using Gradle 8.3 and configuring the Java toolchain's language version #37342
Description
When using GraalVM gradle plugin (v0.9.26) with Spring Boot gradle plugin (v3.1.3), languageVersion cannot be set:
java {
toolchain {
languageVersion.set(JavaLanguageVersion.of(20)) // <-- the error occurs here
}
}
graalvmNative {
binaries {
named("main") {
javaLauncher.set(javaToolchains.launcherFor {
languageVersion.set(JavaLanguageVersion.of(20))
})
}
}
}
The following error occurs:
* What went wrong:
The value for property 'languageVersion' is final and cannot be changed any further.
Here is a reproducer by @jamesward: graalvm/native-build-tools#486 (comment)
Also, @melix explained how to fix it: graalvm/native-build-tools#486 (comment)