Alternative to fatJar - modular solution?

Glavo zjx001202 at
Mon Oct 11 22:48:42 UTC 2021

I mistakenly believe that the implementation of the filesystem corresponds
exactly to the URL. The problem I really want to express is that JDK
does not support URLs of nested jar file systems. It seems that this
problem still exists in JDK 17. To make matters worse, we can use toUri()
to convert the path of the file in the nested jar into a URI, but this
URI is neither accepted by Paths.get (java.lang.IllegalArgumentException:
URI does not contain path info ex. jar:file:/c:/!/BAR) nor
converted into a URL ( Nested JAR URLs
are not supported). Is this a bug or an expected behavior?

Alan Bateman <Alan.Bateman at> 于2021年10月12日周二 上午2:58写道:

> On 11/10/2021 15:09, Glavo wrote:
> > I think this is a great prototype. Based on it, I think such requirements
> > can also be realized by enhancing jar in these aspects:
> >
> >    1. Nested jar file system (The ujar file system seems unnecessary.
> >       I never understand why jar file systems cannot be nested.)
> This was fixed in JDK 12, are you seeing issues with release recent
> releases? If so then would it be possible to submit a bug with a test
> case or bring the issue to core-libs-dev?
> -Alan

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