https://github.com/openjdk/jdk21u/archive/jdk-21.0.9-ga/jdk21u-jdk-21.0.9-ga.tar.gz 
http://www.lenardspencer.net/linux/slackbuilds/OpenJDK-bootstraps/OpenJDK-20.0.2-ga-linux-x86_64-bin.tar.xz 
https://anduin.linuxfromscratch.org/BLFS/OpenJDK/OpenJDK-21.0.2/jtreg-7.3.1+1.tar.gz