There's proguard, originally intended for obfuscation but also serves well for dumping unused code from your project and most importantly from third party libraries. Virtually every Android app has it in its build pipeline, or these days actually a proguard reimplementation by Google (R8) that reads proguard's rather byzantine but effective configuration syntax (you usually need to keep some stuff in libraries that talk to themselves only via reflection)

I think if you do Graal native compilation then you'd effectively get that. The linker should chuck unused code. (though tbh I haven't tried it myself)

But to just say "no reflection" and tree shake your JVM code - not that I'm aware of unfortunately! I'd love to just treeshake entire unused dependencies. At the moment I do it manually - but it's a chore and it's hard to do comprehensively.

Now that post- Java8 you're supposed to jlink the JRE, I somehow doubt this will ever happen. The people that care about executable size would probably be doing Graal Native.

I've used proguard to remove unused classes from dependencies.

Proguard is usually the tool to do that (commonly used on Android with its newest incarnation named R8).

You do need to manually annotate classes used by reflection so it doesn't remove (or obfuscate) them.