A few question about jvm target (again)

So I tested the 4.2.0 feature of adding a folder full of jars with ‘–java-lib’ argument, and it didn’t work. Java failed with “An unexpected error occurred while trying to open file”. It seems I’m stuck with this issue: [jvm] An unexpected error occurred while trying to open file Main.jar · Issue #9775 · HaxeFoundation/haxe · GitHub but I’m not sure. Using the “–java-lib-extern” and adding the jar folder to the class path manually works, so it seems that the issue is all about a lot of jars beeing added to MANIFEST.MF in the jar. But anyway using “–java-lib-extern” is not convinient, so is there I way I can fix that in my project?

Is it possible to build a so called “fat jar” with Haxe? Fat jars are jar files that contains all it’s dependencies in itself. Jar files are zip-files by nature, so it shouldn’t be that hard, right? Maybe there might be some troubles that different jar files have different manifests, I don’t know.

How do I convert Java types to Haxe types in general? For example the libraries that I use return java.util.Date object, what is a proper way to convert it to haxe.Date? Google doesn’t help me with this one. What about other types?