Criar um autocomplete

final AutoCompleteIdField fieldGruInicial = new AutoCompleteIdField("gruInicial",
				new PropertyModel<Integer>(this, "gruInicial.codigo"),
				new PropertyModel<String>(this, "gruInicial.descricao")) {
					private static final long serialVersionUID = 1L;

					@Override
					protected Iterator<Pair<Integer, String>> getChoices(String input)
					{
						Conta filtro = new Conta();
						filtro.setDescricao(input);

						QueryObject<Conta> queryObject = new QueryObject<Conta>(filtro);
					    queryObject.addOrdenacao("descricao", true);
						queryObject.addFetch(QueryObject.innerJoin("plano"));
					    queryObject.addFetch(QueryObject.innerJoin("plano.tipo"));
						queryObject.addRestricao(Restrictions.eq("plano#tipo.nome","PLANO_GRUPOS_FATURAMENTO"));
						queryObject.addRestricao(Restrictions.eq("tipo.nome","GRUPO_FATURAMENTO"));

						Iterator<Conta> iterator = contaService.findContas(queryObject).iterator();
						ArrayList<Pair<Integer, String>> result = new ArrayList<Pair<Integer, String>>();

						while (iterator.hasNext())
						{
							Conta objeto = iterator.next();
							result.add(new Pair<Integer, String>(objeto.getCodigo(),
								objeto.getDescricao()));
						}

						return result.iterator();
					}
				}.addInputBehaviour(new UpperCaseBehavior());