RFR [9] 8176772: jar tool support to report automatic module names

[Chris Hegarty]

> On 15 Mar 2017, at 17:30, Mandy Chung <mandy.chung at oracle.com> wrote:
> 
> ...
> provides and main class, if present. 
> 
> The modifier of ModuleDescriptor will have AUTOMATIC and so all packages are exported and open implicitly and not shown in the output which is okay.

This is a good idea. Here’s an example:

jar --describe-module --file describeAutomaticModule/foo.jar 
No module descriptor found. Derived automatic module.

module foo at 1.2-SNAPSHOT (automatic)
  requires mandated java.base
  contains foo
  main-class foo.Main

---

Updated webrev:
  http://cr.openjdk.java.net/~chegar/8176772.01/

-Chris.