Doc Bug: Building benchmark module requires OpenJDK 21

[orivat]

Describe the bug

Doc states

https://www.keycloak.org/keycloak-benchmark/benchmark-guide/latest/building-benchmark

Building the benchmark module
Build the Keycloak Benchmark module from the sources to run customized tests or the latest nightly changes. There are also pre-built binaries to download.

Prerequisites
Git repository https://github.com/keycloak/keycloak-benchmark checked out

Java Version 11 installed

Maven installed

Version

KC 25.0.4

Expected behavior

Successful compilation

Currently failing with error message:
Fatal error compiling: error: invalid target release: 21

Actual behavior

mvn -f benchmark/pom.xml clean install
[INFO] Scanning for projects...
[INFO]
[INFO] -------------< org.keycloak.benchmark:keycloak-benchmark >--------------
[INFO] Building keycloak-benchmark 0.14-SNAPSHOT
[INFO] from pom.xml
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- clean:3.2.0:clean (default-clean) @ keycloak-benchmark ---
[INFO] Deleting /home/testuser/dev_2024/keycloak-benchmark/benchmark/target
[INFO]
[INFO] --- scala:4.8.1:add-source (add-source) @ keycloak-benchmark ---
[INFO] Add Source directory: /home/testuser/dev_2024/keycloak-benchmark/benchmark/src/main/scala
[INFO] Add Test Source directory: /home/testuser/dev_2024/keycloak-benchmark/benchmark/src/test/scala
[INFO]
[INFO] --- resources:3.3.1:resources (default-resources) @ keycloak-benchmark ---
[INFO] Copying 5 resources from src/main/resources to target/classes
[INFO]
[INFO] --- compiler:3.11.0:compile (default-compile) @ keycloak-benchmark ---
[INFO] Changes detected - recompiling the module! :source
[INFO] Compiling 8 source files with javac [debug target 21] to target/classes
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.224 s
[INFO] Finished at: 2024-08-28T09:31:47+02:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.11.0:compile (default-compile) on project keycloak-benchmark: Fatal error compiling: error: invalid target release: 21 -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

How to Reproduce?

1. Using OpenJDK 11
2. running command
   mvn -f benchmark/pom.xml clean install

Anything else?

It works fine when JDK in use is JDK 21

[Alexander Schwartz]

Thanks for reporting this. I've updated the docs to ask for JDK21 to be installed. The change should be visible online once the build is complete in a few minutes.