RFR:8170868: DefaultProxySelector should use system defaults on Windows, MacOS and Gnome

[Langer, Christoph]

Hi Chris, Arno,

as for a few points:

> 1) It seems awful to have to deal with LinkedList in native code. How
>     about returning an array from native, and then converting that into
>     whatever list type is appropriate at the Java level.
+1

> 2) I would prefer the use of List.of(...), and list.of() for empty, since
>     these are immutable and efficient list implementations.

This seems like a good API to use here. But it only exists in Java 9. So in case of downporting this to Java 8 (which we certainly want to do for our SAP JVM) we need an alternative, which could be the current way of doing it.

> 4) Can some of the native initialization code be moved to a platform
>     independent location, to remove duplication?
+1

> 5) The new file has a shared copyright header. I see similar SAP
>     headers in a few files, but none shared with the Oracle header.
>     How did you arrive at this format?

This format is used at some places, for instance in files of the the os/aix port in hotspot. I just pick hotspot/src/os/aix/vm/attachListener_aix.cpp as the first one but there are more in this subdirectory. Is it appropriate? - I don't know...

Best regards
Christoph