JDK 8 RFR, redux, for JDK-8005294 : Consider default methods for additions to AnnotatedElement

[Joel Borggrén-Franck]

Hi Joe, Peter,

On 29 okt 2013, at 07:09, Joe Darcy <joe.darcy at oracle.com> wrote:
> 
> Your comments, along with some spec refinements from the other OpenJDK list, are reflected in the next iteration of the webrev:
> 
>     http://cr.openjdk.java.net/~darcy/8005294.5/
> 
> Thanks,
> 

259          if (result.length == 0 && // Neither directly nor indirectly present
 260              this instanceof Class && // the element is a class
 261              AnnotationType.getInstance(annotationClass).isInherited()) { // Inheritable
 262              ...

j.l.Class is final and has an implementation of getAnnotationsByType so everything in this branch is dead code. I understand you might want to document how the lookup is supposed to happen if you have inheritance semantics for your AnnotatedElement but IMHO this isn't the way to do it. Just delegate to getDeclaredAnnotationsByType.

291      * @since 1.8
 292      */

 293     default <T extends Annotation> T getDeclaredAnnotation(Class<T> annotationClass) {

I keep forgetting that this one is new to 8. My reservations about making this a default was based on (the misconception) that this was a 5 method. This method looks good.

For getDeclaredAnnotationsByType() the idea of having two implementations of the same logic, one taking arrays as arguments and the other Maps, seems wrong. I would strongly prefer if we only had one implementation, calling into AnnotationSupport from this method. Something like

 default <T extends Annotation> T[] getDeclaredAnnotationsByType(Class<T> annotationClass) {
         Objects.requireNonNull(annotationClass);
	 return AnnotationSupport.getDirectlyAndIndirectlyPresent(Arrays.stream(getDeclaredAnnotations()).collect(Collectors.toMap(
                        (a -> a.getClass()),
                        Function.identity())),
                 annotationClass);
  }

I can't see these default methods as the code we should be spending time optimizing.

cheers
/Joel