[jboss-dev-forums] [Embedded JBoss Development] - SHRINKWRAP-104: Empty Directories

[ALRubinger]

https://jira.jboss.org/jira/browse/SHRINKWRAP-104

I've added support for empty directories (and tests) in r3836.  This is nice, because importers can now account for empty dirs as well.

The design I've used is a new Asset implementation:

public enum DirectoryAsset implements Asset {
  | 
  |    /**
  |     * Singleton Instance
  |     */
  |    INSTANCE;
  | 
  |    /**
  |     * {@inheritDoc}
  |     * @see org.jboss.shrinkwrap.api.Asset#openStream()
  |     */
  |    @Override
  |    public InputStream openStream()
  |    {
  |       // To signify that we've got nothing to back us (we're just a directory),
  |       // we use null.  A stream backed by an empty byte array would be an 
  |       // empty file, which is different.
  |       return null;
  |    }
  | 
  | }

This sucks because:

1) We don't really obey the contract of "Asset", returning a null reference on "openStream"
2) The implementation relies upon "instanceof" runtime type checking to do things like creating directories in the exporter.  Meaning we're checking for a specific implementation.

An alternate approach is to add:

Asset.isDirectory()

...to all Asset types.  In this case "DirectoryAsset.openStream" would still return null, but we could do "Asset.isDirectory" instead of the runtime type checking.

Which is uglier to you?

S,
ALR

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