Join tables in eclipselink (jpa) - sql

Question

I'm trying to convert a simple sql statement to jpql but vainly. I have an entity "Banque" that has many "Compte" and i'm trying to get all the "Compte" for a specific "Banque" using id_Banque.
This is the sql statement :
SELECT COMPTE.* FROM COMPTE INNER JOIN BANQUE ON COMPTE.ID_BANQUE=BANQUE.ID_BANQUE;
============================Entity Banque=========================
#Entity
#Table(name="BANQUE")
public class Banque implements Serializable{
#Id
#GeneratedValue(strategy=GenerationType.AUTO, generator="banque_seq_gen")
#SequenceGenerator(name="banque_seq_gen", sequenceName="BANQUE_SEQ", allocationSize = 1, initialValue = 1)
private Long id_banque;
#OneToMany(cascade = CascadeType.PERSIST, fetch = FetchType.LAZY, mappedBy = "Banque")
private Set<Compte> comptes;
public Banque(){
}
}
============================Entity Compte=========================
#Entity
#Table(name="COMPTE")
public class Compte implements Serializable{
#Id
#GeneratedValue(strategy=GenerationType.AUTO, generator="compte_seq_gen")
#SequenceGenerator(name="compte_seq_gen", sequenceName="COMPTE_SEQ", allocationSize = 1, initialValue = 1)
private Long id_compte;
#ManyToOne(cascade = CascadeType.PERSIST, fetch = FetchType.LAZY)
#JoinColumn(name = "ID_BANQUE")
private Banque Banque;
public Compte(){
}
}
And the following method help me to get all the comptes (Entity compte) associated to a specific Banque (from id_banque) :
public Set<Compte> getComptesFromIdBanque(Long id_banque){
EntityManager em=new JPAContainerFactory().createEntityManagerForPersistenceUnit("addressbook");
Query query = em.createQuery("SELECT c FROM Compte c INNER JOIN c.Banque b WHERE b.id_banque = :id_banque");
query.setParameter("id_banque", id_banque);
Set<Compte> comptes = new HashSet<>(query.getResultList());
return comptes;
}
This is an illustration of the two tables and what i'd like to have :
Then a display this list of comptes in a ComboBox :
compteCombo.addItems(saut.getComptesFromIdBanque(banque.getId_banque()));
compteCombo.setItemCaptionPropertyId("numero");
Unfortunately this doesn't show any item in the comboBox.
I hope i will find a pertinent answer as i searched for this in vain. It'll help me a lot.
Thanks.

Answer 1

Your JPA query seems fine to me (although as #Davids mentioned it could be simplified to SELECT c FROM Compte c WHERE c.banque.id_banque = :id_banque).
My guess is your ComboBox caption is not set up properly to show anything.
First, write a test to make sure your JPA function returns the right data. Then play around with the setItemCaptionMode of ComboBox to get the right setting. Assuming your Compete class has a getNumero() method, you can set up your Combobox like this:
compteCombo = new ComboBox( "Caption", saut.getComptesFromIdBanque(banque.getId_banque()) );
compteCombo.setItemCaptionMode( ItemCaptionMode.PROPERTY );
compteCombo.setItemCaptionPropertyId( "numero" );