[hibernate-dev] Jandex, scanning and discovery

[Hardy Ferentschik]

On 28 Jan 2014, at 17:20, Steve Ebersole <steve at hibernate.org> wrote:

> Almost done with this.  We are much more aggressive about indexing stuff into Jandex now (which is a good thing) when we are not handed a Jandex Index.  
> 
> However, this does mean we need to be more careful in the case of JPA and exclude-non-listed-classes.  ATM we drive annotations based on Jandex (aka, the classes known to Jandex).  However, if we know index classes that should not be used as entities, etc (because of exclude-non-listed-classes) we are breaking the JPA spec.  To this end, I suggest that scanning:
> 1) Index everything
> 2) Keep a running tab of "allowable managed classes and packages".
> 
> Later, when beginning interpretation of annotations (via Jandex) we can cross-reference that with the list of allowable managed classes.  Currently we do:
> 
> for ( ClassInfo classInfo : bindingContext.getJandexAccess().getIndex().getKnownClasses() ) {
>     // use them all...
> }
> 
> 
> What I am suggesting is:
> 
> interface ManagedClassFilter {
>     public boolean allowAsManagedClass(ClassInfo classInfo);
> }
> 
> for ( ClassInfo classInfo : bindingContext.getJandexAccess().getIndex().getKnownClasses() ) {
>     if ( !managedClassFiler.allowAsManagedClass( classInfo ) ) {
>         continue;
>     }
> }
> 
> Further, rather than maintaining potentially large lists of allowable class and package names, I'd also suggest we recognize the cases when we have open-ended discovery in play and simply use an "all inclusive" strategy.  

sounds good.