9
Amper – Improving the Build Tooling User Experience | The JetBrains Blog
(blog.jetbrains.com)
For discussing Java, the JVM, languages that run on the JVM, and other related technologies.
Yes, this seems to have improved, just successfully made a project with gradle and it works with java 18. About 2 years ago it wasn't possible to use Flutter with Java 9, at all.