Message11857

I was playing with the jdk9+ issues on a separate branch.

If you go to https://github.com/ohumbel/jython/tree/jdk9 and scroll down to the README you can find a table of the different encoding determination methods on some platforms.
To summarize:

 - the discouraged internal encoding() method only has an effect on windows
 - there it returns the 'old' DOS code pages
 - on all other platforms, file.encoding equals to defaultCharset()

So my conclusion was to use file.encoding on non windows, and a subprocess 'cmd /c chcp' on windows.

A possible implementation can be found in this commit: https://github.com/ohumbel/jython/commit/8fdf2c762aa054b7525eaaaf853b4e6a7bd69134

If this sounds reasonable, I would be happy to distill this into a new issue2659 branch and create a pull request.