@ManyToMany
@JoinTable(name = "academico.tab_cudi",joinColumns = {
   @JoinColumn(name = "coddisc")},inverseJoinColumns = {
   @JoinColumn(name = "codcurs")
})
private List<TabCurs> codigo;

@ManyToMany(
    cascade = {CascadeType.PERSIST, CascadeType.MERGE},
    mappedBy = "codigo"
)
private List<TabDisc> codigo;

@Override
public void Salvar(TabDisc b) {
    try{
        Session s = HibernateUtil.getSession();
        new CrudUtil<TabDisc>(b, CrudUtil.tipo.INSERT, s);
    }catch(Exception ex){
        ex.printStackTrace();
    }
}

public void execulte() {
    Transaction t = s.getTransaction();
    try {
        switch (op) {
            case INSERT:
                s.saveOrUpdate(obj);
                break;
            case UPDATE:
                s.update(obj);
                break;
            case DELETE:
                s.delete(obj);
                break;
        }
        t.commit();

        s.close();
    } catch (Exception e) {
        t.rollback();
        s.clear();
        s.cancelQuery();
        s.close();
        throw e;
    }
}