Doubt about native query

[Victor Maehira]

Good afternoon!
I�ve downloaded the o'reilly ejb 3.0 book's example code. I was running the source code related to native sql queries when I got a ClassCastException. The snippet source code is the following :

Cruise Entity:

@Entity
@SqlResultSetMapping(name="reservationCount",
                     entities=@EntityResult(entityClass=Cruise.class,
                                            fields=@FieldResult(name="id", column="id")),
                     columns=@ColumnResult(name="resCount"))
public class Cruise implements java.io.Serializable
{
...

Query call:

 ...
 Query query = manager.createNativeQuery("SELECT c.id, count(Reservation.id) as resCount " +
                                              "FROM Cruise c " +
                                              "LEFT JOIN Reservation ON c.id = Reservation.CRUISE_ID " +
                                              "GROUP BY c.id",
                                              "reservationCount");
      List phones = query.getResultList();
      Iterator it = phones.iterator();
      while (it.hasNext())
      {
         Object[] result = (Object[])it.next();
         [B]Cruise cruise = (Cruise)result[1];[/B]         
         [B]int count = (Integer)result[0];[/B]
         System.out.println(cruise.getName() + " " + count);
      }

(The same code can be found on page 623 and 624 of o'reilly book)

The ClassCastException happens in:

Cruise cruise = (Cruise)result[1];

If the result�s index is changed, the application works correctly.

Cruise cruise = (Cruise)result[[B]0[/B]];
      int count = (Integer)result[[B]1[/B]];

How can I justify it?
Thanks in advance!

[Christophe Verré]

Cruise comes first, so as you said, it should be result[0], not result[1].