On 22 November 2012 02:40, Chris Nauroth <cnaur...@hortonworks.com> wrote:
> > It seems like the trickiest issue is preservation of permissions and > symlinks in tar files. I suspect that any JVM-based solution like custom > Maven plugins, Groovy, or jtar would be limited in this respect. According > to Ant documentation, it's a JDK limitation, so I suspect all of these > would have the same problem. I haven't tried any of them though. (If > there was a feasible solution, then Ant likely would have incorporated it > long ago.) If anyone wants to try though, we might learn something from > that. > > Thank you, > --Chris > > You are limited by what File.canRead(), canWrite() and canExecute) tell you. The absence of a way to detect file permissions in Java -is because of the lowest-common-denominator approach of the JavaFS APIs, supporting FAT32 (odd case logic, no perms or symlinks), NTFS (odd case logic, ACLs over perms, symlinks historically very hard to create), HFS+ (case insensitive unix fs!) as well as classic unixy filesystems. Ant <tarfileset> filesets in <tar> let you spec permissions on filesets you pull into the tar; they are generated x-platform, which the other reason why you declare them in <tar> -you have the right to generate proper tar files even if you use a Windows box. symlinks are problematic -even detecting them cross platform is pretty unreliable. To really do them you'd need to add a new <symlinkfileset> entity for <tar>, that would take the link declaration. I could imagine how to do that -and if stuck into the hadoop tools JAR, wouldn't even depend on a new version of Ant. Maven just adds extra layers in the way. -Steve
