QtCreator Java support (Java Language Server)

[morte]

Has someone managed to activate Java Language Server support in QtCreator?

I tried to set it up under Windows 10 & recent QtCreator releases (8,9), but it doesn't works:

there is manual (which is kinda useless) https://doc.qt.io/qtcreator/creator-language-servers.html
tried EclipseRT-OSGi-StarterKit-4.25-win32-win32-x86_64.zip downloaded from https://download.eclipse.org/equinox/drops/R-4.25-202208311800/index.php with JDK 11 (Eclipse Adoptium)