Post-processor callback interface for merged
bean definitions at runtime.
implementations may implement this sub-interface in order
to post-process the merged bean definition (a processed copy of the original bean
definition) that the Spring
uses to create a bean instance.
postProcessMergedBeanDefinition(org.springframework.beans.factory.support.RootBeanDefinition, java.lang.Class<?>, java.lang.String) method may for example introspect
the bean definition in order to prepare some cached metadata before post-processing
actual instances of a bean. It is also allowed to modify the bean definition but
only for definition properties which are actually intended for concurrent
modification. Essentially, this only applies to operations defined on the
RootBeanDefinition itself but not to the properties of its base classes.