RFR: 8252730: jlink does not create reproducible builds on different servers [v9]

[Alan Bateman]

On Fri, 18 Sep 2020 20:40:28 GMT, Ian Graves <igraves at openjdk.org> wrote:

>> Related to [JDK-8252730 jlink does not create reproducible builds on different
>> servers](https://bugs.openjdk.java.net/browse/JDK-8252730). Introduces ordering based on `Archive` module names to
>> ensure stable files (and file signatures) across generated JDK images by jlink.
>
> Ian Graves has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Using File.walk for copy

test/jdk/tools/jlink/JLinkReproducible3Test.java line 112:

> 110:     }
> 111: }
> 112:

The update to ImageFileCreator looks good.

A few nits in JLinkReproducible3Test:
1. Invoking copyJDKs with two destination locations looks a bit strange. I think would be easier for future maintainers
if it does one copy and is called twice. 2. Files.copy will create a directory, no need for Files.createDirectories.
3. Are you sure that bin/jlink is executable, I just wonder if the test runs with the patch have ended up depending the
umask at the time. It is possible to specify COPY_ATTRIBUTES to the copy method and it will attempt to copy the
permissions. 4. The variable naming is more like C style, so a bit inconsistent with the naming usually used in Java
programs.

-------------

PR: https://git.openjdk.java.net/jdk/pull/156