How to save a list using Hibernate?

Question

How to save an entire list using Hibernate? I’m trying to save a list this way:

classe.setMinhaLista(minhaLista);
classeDao.salvar(classe);

And so:

classe.setMinhaLista(new ArrayList<Objeto>());

for(Objeto obj : minhaLista) {
     classe.getMinhaLista().add(obj);
}

classeDao.salvar(classe);

But I’m not getting either way and the glassfish console returns no error.

Entidade Minhalista

@Entity
public class MinhaLista implements Serializable {

private static final long serialVersionUID = 1L;

private Long idMinhaLista;
private Classe classe;

public void setClasse(Classe classe) {
    this.classe = classe
}

@ManyToOne
public void getClasse() {
    return classe;
}

// Restante dos gets e setter omitidos
}

Entity Classe

@Entity
public class Classe implements Serializable {

private static final long serialVersionUID = 1L;

private Long idClasse;
private List<MinhaLista> minhaLista;

public void setMinhaLista(List<MinhaLista> minhaLista) {
    this.minhaLista = minhaLista;
}

@OneToMany(mappedBy = "classe",cascade={CascadeType.ALL})
public List<MinhaLista> getMinhaLista() {
    return minhaLista;
}

// Restante dos getters e setters omitidos
}

Answer 1

I believe the list is being saved because it is empty, if you fill in the objects you can link to the list, tbm it is good to add the class property to the list, so that the system prevents you from saving a list without class

public class Classe {
    private Long id;    
    @OneToMany(mappedBy = "classe",cascade = CascadeType.PERSIST)
    private List<Lista> minhaLista;
}

The PERSIST tab will save the list if it is in mode transient

public class Lista {
    @NotNull
    @ManyToOne(optional = false)
    private Classe classe;
}

The Optional=false will force the field to have a class, Notnull will add a validation and if you are using Hibernate validation, it will prevent you from saving the entire transaction.

And before saving, you must circulate the assignment

classe.getMinhaLista().forEach(lista->lista.setClasse(classe));

Answer 2

I was able to save the list items, all at once, that way:

1. Save each item from the drop-down list to the database and add it to my list

     objeto.setNome(nome);
     objetoDao.salvar(objeto);
     minhaLista.add(objeto);
   

2. Soon after, I walk through the minhalista and update each object, linking it to the class

     for(Objeto obj : minhaLista) {
         obj.setClasse(classe);
         objetoDao.atualizar(obj);
     }