anchor.diff:  
   [TIP]
   ====
  -
   The JSR-250 `@PostConstruct` and `@PreDestroy` annotations are generally considered best
   practice for receiving lifecycle callbacks in a modern Spring application. Using these
   annotations means that your beans are not coupled to Spring specific interfaces. For
  
positive.code: about singletons here.
  ====
  
  [NOTE]
  ====
  There are a few restrictions due to the fact that CGLIB dynamically adds features at
  startup-time:
  
  * Configuration classes should not be final
  * They should have a constructor with no arguments
  ====
  
  
  
negative.code: This approach simplifies container instantiation, as only one class needs to be dealt
  with, rather than requiring the developer to remember a potentially large number of
  `@Configuration` classes during construction.
  
  [TIP]
  ====
  As of Spring Framework 4.2, `@Import` also supports references to regular component
  classes, analogous to the `AnnotationConfigApplicationContext.register` method.
  This is particularly useful if you'd like to avoid component scanning, using a few
  configuration classes as entry points for explicitly defining all your components.
  ====
  
  [[beans-java-injecting-imported-beans]]
  ===== Injecting dependencies on imported @Bean definitions
  