anchor.diff:  ----
   @Entity
   @WriteConcern(WriteConcernType.JOURNALED)
  +@ReadPreference(ReadPreferenceType.PRIMARY_PREFERRED)
   @AssociationStorage(AssociationStorageType.ASSOCIATION_DOCUMENT)
   @AssociationDocumentStorage(AssociationDocumentType.COLLECTION_PER_ASSOCIATION)
   public class Zoo {
  
positive.code: ====
  
  The +@WriteConcern+ annotation on the entity level expresses that all writes should be done using the +JOURNALED+ setting.
  The other two annotations specify that all associations of the +Zoo+
  class should be stored in separate assocation documents, using a dedicated collection per association.
  This setting applies to the +animals+ and +employees+ associations.
  Only the elements of the +visitors+ association will be stored in the document of the corresponding +Zoo+ entity
  
negative.code: When working with MongoDB, you can currently configure the following options using the API:
  
  * write concern
  * read preference
  * association storage strategy
  * association document storage strategy
  
  