RFR: 8163798: Create a JarFile versionedStream method

[Steve Drach]

I guess I’m going to keep doing this until I get it right ;-)  Here’s another webrev that doesn’t use an exception for a common case, and addresses most of Mandy concerns.  

http://cr.openjdk.java.net/~sdrach/8163798/webrev.06/ <http://cr.openjdk.java.net/~sdrach/8163798/webrev.06/>

Comments in-line

> This version looks good.
> 
> Can you add the javadoc to describe what the stream method returns (a union of the base entries + all versioned entries <= JarFile::getVersion.

Done

> 
> Nit:  you may want to call jf.getVersion().major() once rather than the number of entries.

Done

> 
> Now that you have jdk.internal.util.jar internal API for MRJAR.  It may be useful to add a static getRealName(JarFile jar, JarEntry entry) method for convenience such that jdeps and jlink can use this MRJAR-specific internal API and no need to use the shared secret. Maybe rename VersionedStream to VersionedJarFileHelper?
> 
> TestVersionedStream::close
>   You may want to use jdk.testlibrary.FileUtils and deleteFileTreeWithRetry may be what you want.

I can’t use it because it removes the top-level directory (i.e. JTwork/scratch).

> 
> Mandy