[jboss-dev] Improving scanning performance

[Ales Justin]

All of this already exists. ;-)

> * You should have a AnnotationScanner deployer that scans jars for 
> annotations and puts an annotation database somewhere in memory that 
> other deployers can reference.  (This might already exist, I don't know).

It is called AnnotationEnvironment, and it's part of the deployment's 
attachments.

It's already used to help Metadata get annotation info.
But how it's done in Metadata is bad/wrong.

> * If a file META-INF/no.scan exists in a jar, then don't scan the file. 
>  This allows libraries to exclude themselves from scanning.
> 
> * If a file META-INF/scan.only exists it will contain a newline 
> delimited list of class names to scan.  Only scan those class names.

This is called jboss-scanning.xml.
  - http://www.jboss.org/community/wiki/JBoss5custommetadatafiles

We already exclude all of our boot.
See metadata-deployer-jboss-beans.xml:
  - 
http://anonsvn.jboss.org/repos/jbossas/branches/Branch_5_x/server/src/etc/deployers/metadata-deployer-jboss-beans.xml