Request for approval: 8160174: java.net.NetworkInterface - fixes and improvements for network interface listing

[Langer, Christoph]

Hi Chris,

I understand your concerns regarding too much change here which could result in subtle differences that might not be wanted for a released version.

The main motivation for me to integrate the change into JDK 8 is mergeability. In our SAP JVM 8 we had the need to do several fixes for problems on various of our supported platforms. And with the current coding layout it is very hard to do fixes, especially for AIX/Linux as all the #ifdefs make it a mess. So we already stepped to a version of code that merely matches the JDK9 version.

But I agree that with my proposal (http://cr.openjdk.java.net/~clanger/webrevs/8160174.8udev/) I'm probably touching unnecessary places and make a review really hard.

What about this proposal for downporting the fix to Bug 8158519:
http://cr.openjdk.java.net/~clanger/webrevs/8158519.8udev/

Here I really only split the enumIPv*Interfaces methods to a clean structure and then make the necessary changes to eliminate getBroadcast() and getSubnet() functions in order to determine that information correctly in place before calling addif.

Could you give a review for that?

Thanks a lot
Christoph



> -----Original Message-----
> From: Chris Hegarty [mailto:chris.hegarty at oracle.com]
> Sent: Donnerstag, 18. August 2016 17:49
> To: Langer, Christoph <christoph.langer at sap.com>
> Cc: jdk8u-dev at openjdk.java.net; Rob McKenna <rob.mckenna at oracle.com>
> Subject: Re: Request for approval: 8160174: java.net.NetworkInterface - fixes
> and improvements for network interface listing
> 
> On 16 Aug 2016, at 15:41, Rob McKenna <rob.mckenna at oracle.com> wrote:
> >
> > Hi Christoph,
> >
> > If the patch has changed from 9 you will need a separate review.
> >
> > 	-Rob
> >
> > On 16/08/16 10:09, Langer, Christoph wrote:
> >> Hi,
> >>
> >> can I get approval for backporting the following fix:
> >>
> >>
> >> Original Bug: https://bugs.openjdk.java.net/browse/JDK-8160174
> >>
> >> Jdk9 change: http://hg.openjdk.java.net/jdk9/dev/jdk/rev/a8db670c7d12
> >>
> >> Jdk9 review thread: http://mail.openjdk.java.net/pipermail/net-dev/2016-
> July/010100.html
> >>
> >>
> >> I had to modify the jdk9 patch after unshuffling to get it to apply to 8udev.
> This is the new webrev:
> http://cr.openjdk.java.net/~clanger/webrevs/8160174.8udev/
> 
> Wow, there are quite a lot of changes in this. I do remember reviewing this for
> 9 ( it
> took a long time ).  I do have a concern that this change may cause some subtle
> behavioural differences, since the underlying systems calls may be different.
> This
> may be acceptable for a major release, but not so for an update release.
> 
> Is there a strong need for this to be backported?
> 
> -Chris.