selectOneMenu choose everything and depending on a column - sql

Question

hi i have a question i have a selectOneMenu and depending on the value chosen i display my datatable but i want when i open my jsf page at first to display all the rows and also if i choose everything in the selectOneMenu to display all the rows. how i could do that.
JSF :
<h:panelGrid columns="2" cellpadding="5">
<h:outputText value="Annee : " style="font-size: 18px" />
<p:selectOneMenu value="#{anneeBean.annee}" >
<f:selectItem itemValue="#{null}" itemLabel="--Séléctionner une année--" />
<f:selectItems value="#{anneeBean.listeAnnees}" var="annee"
itemValue="#{annee}" itemLabel="#{annee}" />
<f:ajax listener="#{anneeBean.submit()}" render="display" />
</p:selectOneMenu>
</h:panelGrid>
Hibernate
#Override
public List getAllBudgets(Integer id) {
Session session=HibernateUtil.getSession();
try
{
session.beginTransaction();
Query q = session.createQuery("from Budgetisation as b left join fetch b.rubrique as r left join fetch b.annee where b.id.annee=:annee");
q.setParameter("annee", id);
listeBudgets = q.list();
return listeBudgets;
}
catch(HibernateException e)
{
throw e;
}
finally
{
session.close();
}
}