What does HackerNews think of FlatLaf?

JVM UI isn't so bad. I've written some pretty modern looking UI with it. The sophisticated controls are all there.

Modern JavaFX theme: https://github.com/mkpaz/atlantafx

Modern Swing theme: https://github.com/JFormDesigner/FlatLaf

And these days Compose Multiplatform: https://www.jetbrains.com/lp/compose-multiplatform/

I tend to use Kotlin rather than Java but of course Java is perfectly fine too. You can also use Clojure.

If you use any of those frameworks you can distribute to Win/Mac/Linux in one command with Conveyor. It's free for open source apps and can do self-signing for Windows if you don't want to pay for the certificates or the Store (but the Store is super cheap these days, $19 one off payment for an individual). Also supports Electron and Flutter if you want to use those.

From those frameworks you can then access whatever parts of the Windows API you want. Flutter even has WinRT bindings these days! So it's not quite so bad.

Take a look at FlatLAF:

https://github.com/JFormDesigner/FlatLaf

They have done a great job bringing a modern appearance to the Swing components.

If you are looking to use Java. This is very good

https://github.com/JFormDesigner/FlatLaf

There’s also Kotlin multi platform