Prior to this commit, and based on earlier changes supporting SPR-9023,
ConfigurationClassBeanDefinitionReader employed a simplistic strategy
for extracting the 'value' attribute (if any) from @Configuration in
order to determine the bean name for imported and nested configuration
classes. An example case follows:
@Configuration("myConfig")
public class AppConfig { ... }
This approach is too simplistic however, given that it is possible in
'configuration lite' mode to specify a @Component-annotated class with
@Bean methods, e.g.
@Component("myConfig")
public class AppConfig {
@Bean
public Foo foo() { ... }
}
In this case, it's the 'value' attribute of @Component, not
@Configuration, that should be consulted for the bean name. Or indeed if
it were any other stereotype annotation meta-annotated with @Component,
the value attribute should respected.
This kind of sophisticated discovery is exactly what
AnnotationBeanNameGenerator was designed to do, and
ConfigurationClassBeanDefinitionReader now uses it in favor of the
custom approach described above.
To enable this refactoring, nested and imported configuration classes
are no longer registered as GenericBeanDefinition, but rather as
AnnotatedGenericBeanDefinition given that AnnotationBeanNameGenerator
falls back to a generic strategy unless the bean definition in question
is assignable to AnnotatedBeanDefinition.
A new constructor accepting AnnotationMetadata
has been added to AnnotatedGenericBeanDefinition in order to support
the ASM-based approach in use by configuration class processing. Javadoc
has been updated for both AnnotatedGenericBeanDefinition and its now
very similar cousin ScannedGenericBeanDefinition to make clear the
semantics and intention of these two variants.
Issue: SPR-9023