Gradle 8.7 cannot find installed JDK 22 in IntelliJ

Question

I have created a new project with IntelliJ IDEA Ultimate version 2024.1. This version supports the new Java 22 (openjdk-22) version. But when I reload my Gradle project, it shows this error:

Unsupported Gradle JVM.
Your build is currently configured to use Java 22 and Gradle 8.7.
Possible solutions:

- Use Java 21 as Gradle JVM: Open Gradle settings
- Upgrade to Gradle 8.5 and re-sync

AND THIS:

FAILURE: Build failed with an exception.

* What went wrong:
BUG! exception in phase 'semantic analysis' in source unit '_BuildScript_' Unsupported class file major version 66
> Unsupported class file major version 66

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

CONFIGURE FAILED in 69ms

Under "project structure" I have selected the installed Java 22 SDK. Also, all Modules are of the SDK Default Language Level.

These are my Gradle properties:

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-bin.zip
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists

and this is my build.kts:

plugins {
    id("java")
}

group = "org.example"
version = "1.0-SNAPSHOT"

repositories {
    mavenCentral()
}

java {
    sourceCompatibility = JavaVersion.VERSION_22
    targetCompatibility = JavaVersion.VERSION_22

}
dependencies {
    testImplementation(platform("org.junit:junit-bom:5.10.0"))
    testImplementation("org.junit.jupiter:junit-jupiter")
}

tasks.test {
    useJUnitPlatform()
}

Answer 1

Gradle 8.7 does not run on Java 22

The problem is not that IntelliJ-IDEA doesn't support Java 22. The problem is that Gradle does not run on Java 22 (it only supports building projects for Java 22 but must be run with Java 21 maximum).

From the Gradle 8.7 release notes:

Support for building projects with Java 22

Gradle now supports using Java 22 for compiling, testing, and starting other Java programs. Selecting a language version is done using toolchains.

You cannot run Gradle 8.7 itself with Java 22 because Groovy still needs to support JDK 22. However, future versions are expected to provide this support.