[MRJAR] Entry order matters?

[Robert Scholte]

Hi,

we have this demo application[1] to show how you can generate a  
multirelease JAR right now with Maven.
However, in my case the result for Java9 is very unstable. Most of the  
time I get something like
9-ea+133-jigsaw-nightly-h5435-20160828
BASE

but I would expect
9-ea+133-jigsaw-nightly-h5435-20160828
 FROM BASE -> NINE

Once I had both a successful and a failing jar, I compared the content:
success:
META-INF/MANIFEST.MF
META-INF/
base/
mr/
META-INF/maven/
META-INF/maven/multirelease/
META-INF/maven/multirelease/multirelease-base/
META-INF/versions/
META-INF/versions/8/
META-INF/versions/8/mr/
META-INF/versions/9/
META-INF/versions/9/mr/
base/Base.class
META-INF/maven/multirelease/multirelease-base/pom.properties
META-INF/maven/multirelease/multirelease-base/pom.xml
META-INF/versions/8/mr/A.class
mr/A.class
META-INF/versions/9/mr/A.class

failure:
META-INF/MANIFEST.MF
META-INF/
base/
mr/
META-INF/versions/
META-INF/versions/8/
META-INF/versions/8/mr/
META-INF/versions/9/
META-INF/versions/9/mr/
base/Base.class
META-INF/maven/multirelease/
META-INF/maven/multirelease/multirelease-base/pom.properties
META-INF/versions/9/mr/A.class
META-INF/versions/8/mr/A.class
META-INF/maven/multirelease/multirelease-base/pom.xml
mr/A.class
META-INF/maven/multirelease/multirelease-base/
META-INF/maven/

AFAIK the JEP238 doesn't mention something about order.
This is an issue on both Windows and Mac.
Anyone who has an explanation?

regards,
Robert Scholte

[1] https://github.com/hboutemy/maven-jep238
[2] http://openjdk.java.net/jeps/238