anchor.diff:  public interface PersonRepository extends QueryDslSupport
   {
      ...
  -}   
  +}
   ---------------------------------------------------------
   
   === Implementing the Query Delegate
  
positive.code: ---------------------------------------------------------------------------------------------
  @NamedQuery(name = Person.BY_MIN_AGE,
              query = "select count(p) from Person p where p.age > :minAge order by p.age asc")
          
  ...
  
  @Repository
  
negative.code: * Followed by a property of the Repository entity and an optional comparator (we'll define this later). The property will be used in the query together with the comparator. Note that the number of arguments passed to the method depend on the comparator.
  * You can add more blocks of property-comparator which have to be concatenated by a boolean operator. This is either an `And` or `Or`.
  
  You can also use the same way for delete an entity:
  * It must start with the `removeBy` keyword (or related `deleteBy`).
  
  or for counting:
  * It must start with the `countBy` keyword.
  * It must return a int or long.
  
  Other assumptions taken by the expression evaluator:
  
  