I hope this article is superfluous by the time you're reading it. But at the time of writing, installing GraalVM on a Mac isn't that easy. I've been googling for the solution at least three times, so I've decided to document the solution here.
Basically, installing GraalVM is a walk in the park. Download the GraalVM package bearing "Darwin" in its name. Unpack it and copy the folder to /Library/Java/JavaVirtualMachines/. Now GraalVM is almost ready for use. Almost.
Do-it-yourself notarization
Published by annca on Pixabayunder a Pixabay license.There's just one thing left to do. Every application that wants to run on a modern OSX needs to be "notarized". As far as I know, this security mechanism has been introduced with the Catalina version. For some reason, the GraalVM team hasn't applied for notarization yet, so it's up to you to get GraalVM out of quarantine. Like so often, that's a single line of code - plus a couple of hours of research to find it: sudo xattr -r -d com.apple.quarantine /Library/Java/JavaVirtualMachines/graalvm-ce-java11-20.0.0
It goes without saying you'll want to adapt the folder name. The important bit is to apply the statement to the root folder.
Caveat: The xattr command overrides an important security mechanism of your operation system. You're playing with fire. Please double-check you've downloaded GraalVM from a reliable source!
Dig deeper
https://github.com/oracle/graal/issues/1724 the GitHub ticket that finally helped me