/**
  * Adds or update all the persistent entities.
  *
  * @param entities The entities to be persisted.
  * @return The persisted (and updated) entity.
  */
 public Collection<FakeEntity> addOrUpdate(final Collection<FakeEntity> entities) {
   // Validates the new fakeEntity.
   fakeEntityBusinessRuleSet.validate(entities);
   // Merges the entities.
   return fakeEntityDAO.merge(entities);
 }
 /**
  * Adds or update the persistent entity.
  *
  * @param fakeEntity The entity to be persisted.
  * @return The persisted (and updated) entity.
  */
 public FakeEntity addOrUpdate(final FakeEntity fakeEntity) {
   // Validates the new fakeEntity.
   fakeEntityBusinessRuleSet.validate(fakeEntity);
   // Merges the fakeEntity.
   return fakeEntityDAO.merge(fakeEntity);
 }