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Area

core

Describe the bug

I am trying to compile Keycloak 25.0.1 from source, but I am encountering an error related to Java version mismatches.

I am using Java 21, but when running the build, I get the following error message:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project keycloak-common: Fatal error compiling: error: release version 8 not supported

Environment:
Keycloak version: 25.0.1
Java version: 21.0.3 (LTS)
Apache Maven version: 3.9.6
Operating system: Linux (aarch64)

Version

25.0.1

Regression

• The issue is a regression

Expected behavior

I expect the build to complete successfully using Java 21.

Actual behavior

I am encountering the error:
Fatal error compiling: error: release version 8 not supported.

How to Reproduce?

Clone the Keycloak repository.
Checkout to the 25.0.1 tag.
Run the following command to build Keycloak:

./mvnw clean install -pl services -am

Anything else?

No response