Developing #Java with #Gradle on #NixOS and needing multiple or different specific #JDK(s) (toolchain versions) might be a tricky with NixOS, as it's not following FHS and installed JDK(s) aren't placed in standard Linux locations.
Sharing a configuration to be added/imported into `configuration.nix`, that makes multiple JDK(s) available in /opt/java, and therefore Gradle's JDK auto-detection picks them.
https://discourse.nixos.org/t/system-wide-installation-of-gradle-and-jdk/11305/4?u=kravemir
