ejbHome( )
CMP and
BMP entity beans can declare home
methods
that perform operations related to the
EJB component but that are not specific to an entity bean instance. A
home method must have a matching implementation in the bean class
with the signature
ejbHome<
METHOD-NAME
>( )
.
For example, the Cruise EJB might define a home method that calculates the total revenue in bookings for a specific Cruise:
public interface CruiseHomeLocal extends javax.ejb.EJBLocalHome {
public CruiseLocal create(String name, ShipLocal ship);
public double totalReservationRevenue(CruiseLocal cruise);
}
Every home method declared by the home interfaces must have a
corresponding
ejbHome<
METHOD-NAME
>( )
in the bean class. For example, the
CruiseBean
class would have an
ejbHomeTotalReservationRevenue( )
method, as shown
in the following code:
public abstract class CruiseBean implements javax.ejb.EntityBean { public Integer ejbCreate(String name, ShipLocal ship) { setName(name); } ... public double ejbHomeTotalReservationRevenue(CruiseLocal cruise) { Set reservations = ejbSelectReservations(cruise); Iterator it = reservations.iterator( ); double total = 0; while(it.hasNext( )) { ReservationLocal res = (ReservationLocal)it.next( ); total += res.getAmount( ); } return total; } public abstract ejbSelectReservations(CruiseLocal cruise); ... }
The ejbHome( )
methods execute without an identity
within the instance pool. This is why
ejbHomeTotalReservationRevenue( )
required that a
CruiseLocal
EJB object reference ...
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