SPR-11512 introduced support for annotation attribute aliases via
@AliasFor, requiring the explicit declaration of the 'attribute'
attribute. However, for aliases within an annotation, this explicit
declaration is unnecessary.
This commit improves the readability of alias pairs declared within an
annotation by introducing a 'value' attribute in @AliasFor that is an
alias for the existing 'attribute' attribute. This allows annotations
such as @ContextConfiguration from the spring-test module to declare
aliases as follows.
public @interface ContextConfiguration {
@AliasFor("locations")
String[] value() default {};
@AliasFor("value")
String[] locations() default {};
// ...
}
Issue: SPR-13289
In addition to specifying the event type to listen to via a method
parameter, any @EventListener annotated method can now alternatively
define the event type(s) to listen to via the "classes" attributes (that
is aliased to "value").
Something like
@EventListener({FooEvent.class, BarEvent.class})
public void handleFooBar() { .... }
Issue: SPR-13156
Prior to this commit, the implementation of getRepeatableAnnotation()
in Spring's AnnotationUtils complied neither with the contract of
getAnnotationsByType() nor with the contract of
getDeclaredAnnotationsByType() as defined in AnnotatedElement in Java 8.
Specifically, unexpected results can be encountered when using Spring's
support for @Repeatable annotations: either annotations show up in the
returned set in the wrong order, or annotations are returned in the set
that should not even be found based on the semantics of @Repeatable.
This commit remedies this problem by deprecating the existing
getRepeatableAnnotation() methods and replacing them with new
getRepeatableAnnotations() and getDeclaredRepeatableAnnotations()
methods that comply with the contracts of Java's getAnnotationsByType()
and getDeclaredAnnotationsByType(), respectively.
Issue: SPR-13068
In AnnotatedElementUtils, all methods pertaining to merging annotation
attributes have been renamed to "getMerged*()" and "findMerged*()"
accordingly. Existing methods such as getAnnotationAttributes(..) have
been deprecated in favor of the more descriptive "merged" variants.
This aligns the naming conventions in AnnotatedElementUtils with those
already present in AnnotationReadingVisitorUtils.
The use of "annotationType" as a variable name for the fully qualified
class name of an annotation type has been replaced with
"annotationName" in order to improve the readability and intent of the
code base.
In MetaAnnotationUtils.AnnotationDescriptor, getMergedAnnotation() has
been renamed to synthesizeAnnotation(), and the method is now
overridden in UntypedAnnotationDescriptor to always throw an
UnsupportedOperationException in order to avoid potential run-time
ClassCastExceptions.
Issue: SPR-11511
Stephane Nicoll
Sam Brannen
Juergen Hoeller