ListView with Hibernate 3 not popula

I have the class below, the listarGeneroTreeView () method, captures the values I have in the database. However, I am not able to display this data in the treeview. I know only that it works by a message that I inserted to know if it was right.

public class RootLayoutController implements Initializable {

@FXML
private TextField txtPesquisa = new TextField();
@FXML
private Label lblStatus = new Label();
@FXML
private ProgressBar pbProgressBar = new ProgressBar();
@FXML
private TreeView<String> tvGenero;
@FXML
private TableView<DiscoTabela> tbvDiscos = new TableView();
@FXML
private TableColumn<DiscoTabela, Integer> clId;
@FXML
private TableColumn<DiscoTabela, String> clArtista;
@FXML
private TableColumn<DiscoTabela, String> clAlbum;
@FXML
private TableColumn<DiscoTabela, String> clAno_Gravado;
@FXML
private TableColumn<DiscoTabela, String> clGenero;
@FXML
private Button btnPesquisar = new Button();
@FXML
private Button btnDeletar = new Button();
@FXML
private Button btnEditar = new Button();
@FXML
private Button btnNovo = new Button();
@FXML
private Button btnNovo_Genero = new Button();
@FXML
private Button btnEditar_Genero = new Button();
@FXML
private Button btnDeletar_Genero = new Button();

@SuppressWarnings("unused")
private static final Logger logger = Logger.getLogger(Main.class.getName());


//Parametros para a clase disco
private DiscoDao discoDao = new DiscoDao();
private List<Disco> discoList = discoDao.listDisco();
private ObservableList<DiscoTabela> listDiscoTabela = FXCollections.observableArrayList();

//Parametros para a classe genero
private GeneroDao generoDao = new GeneroDao();
private List<Genero> generoList = generoDao.listGenero();
private ObservableList<String> listGeneroTabela = FXCollections.observableArrayList();

//Parametros para TreeView
private Node rootIcon = null;
private String T;
private TreeItem<String> rootNode = new TreeItem<String> ("Generos");


public void initialize(URL location, ResourceBundle resourcebundle){
    //iniciaTreeView();
    listarGeneroTreeView();
    listarDiscos();
}  


@FXML
public void novo(ActionEvent event) throws IOException{

    Disco tempDisco = new Disco();
    //Disco criteria = discoList.listIterator().next();
    //int nextID = criteria.getId();    

    if(showAddDialog(tempDisco)){
        discoList = discoDao.listDisco();
        listarDiscos();

    }

}

@FXML 
public void novoGenero(ActionEvent event) throws IOException{

    Genero tempGenero = new Genero();
    //int crit = generoList.listIterator().next().getID();
    //int nextID = crit;

    if(showAddGeneroDialog(tempGenero)){
        logger.log(Level.ALL,"");
        generoList = generoDao.listGenero();
        listarGeneroTreeView();
    }
}

@FXML
public void editar(ActionEvent event) throws IOException{

    DiscoTabela disco = tbvDiscos.getSelectionModel().getSelectedItem();
    int id = disco.getID();
    String artista = disco.getArtista();
    String album = disco.getDisco();
    String anoGravado = disco.getAnoGravado();
    String genero = disco.getGenero();


    if(showEditDialog(id, artista, album, anoGravado, genero)){
        discoList = discoDao.listDisco();
        listarDiscos();
    }

}

@FXML
private void editaGenero(ActionEvent event) throws IOException {

}

@FXML
public void deletar(ActionEvent event) throws IOException{
    DiscoTabela disco = tbvDiscos.getSelectionModel().getSelectedItem();
    int id = disco.getID();

    listDiscoTabela.remove(disco);
    discoDao.delete(id);

    discoList = discoDao.listDisco();

    listarDiscos();     
}

@FXML
private void deletaGenero(ActionEvent event) throws IOException{        


}


@FXML
public void pesquisar(ActionEvent event) throws IOException{



}

private boolean showAddGeneroDialog(Genero genero) {
    try{
        FXMLLoader loader = new FXMLLoader();
        loader.setLocation(this.getClass().getResource("/fxml/AdicionaGenero.fxml"));
        BorderPane addGenero = (BorderPane) loader.load();

        Stage dialogStage = new Stage();
        dialogStage.setTitle("Nova Genero");
        dialogStage.initModality(Modality.WINDOW_MODAL);
        dialogStage.initOwner(null);

        Scene cene = new Scene(addGenero);
        dialogStage.setScene(cene);

        //Define a pessoa no Controller
        AdicionaGeneroController controller = loader.getController();
        controller.setDialogStage(dialogStage);
        controller.setGenero(genero);

        dialogStage.showAndWait();

        return controller.isOkClicked();
    }catch (IOException ioe){
        ioe.printStackTrace();
        return false;
    }
}

private boolean showAddDialog(Disco disco){
    try{
        FXMLLoader loader = new FXMLLoader();
        loader.setLocation(this.getClass().getResource("/fxml/Adiciona.fxml"));
        BorderPane addLayout = (BorderPane) loader.load();

        Stage dialogStage = new Stage();
        dialogStage.setTitle("Nova entrada");
        dialogStage.initModality(Modality.WINDOW_MODAL);
        dialogStage.initOwner(null); 

        Scene cene = new Scene(addLayout);
        dialogStage.setScene(cene);

        //Define a pessoa no Controller
        AdicionaController controller = loader.getController();
        controller.setDialogStage(dialogStage);
        controller.setDisco(disco);

        dialogStage.showAndWait();

        return controller.isOkClicked();
    }catch (IOException e){
        e.printStackTrace();
        return false;
    }
}

private boolean showEditDialog(int id, String artista, String album, String anoGravado, String genero){
    try{
        FXMLLoader loader = new FXMLLoader();
        loader.setLocation(this.getClass().getResource("/fxml/Edita.fxml"));
        BorderPane editLayout = (BorderPane) loader.load();

        Stage dialogStage = new Stage();
        dialogStage.setTitle("Editar Artista");
        dialogStage.initModality(Modality.WINDOW_MODAL);
        dialogStage.initOwner(null);

        Scene cene = new Scene(editLayout);
        dialogStage.setScene(cene);         

        EditaController controller = loader.getController();
        controller.setDialogStage(dialogStage);
        controller.setDisco(id, artista, album, anoGravado, genero);

        dialogStage.showAndWait();

        return controller.isOkClicked();
    }catch(IOException e){
        e.printStackTrace();
        return false;
    }
}

public void listarDiscos(){
    if(!listDiscoTabela.isEmpty()){
        listDiscoTabela.clear();
        System.out.print("Limpou tabela");
    }

    for(Disco disco: discoList){

        try {
            DiscoTabela d = new DiscoTabela(disco.getId(), disco.getArtista(), disco.getDisco(), disco.getAnoGravado(), disco.getGenero());
            listDiscoTabela.add(d);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }


    clId.setCellValueFactory(new PropertyValueFactory<DiscoTabela, Integer>("id"));
    clAlbum.setCellValueFactory(new PropertyValueFactory<DiscoTabela, String>("disco"));
    clArtista.setCellValueFactory(new PropertyValueFactory<DiscoTabela, String>("artista"));
    clAno_Gravado.setCellValueFactory(new PropertyValueFactory<DiscoTabela, String>("anoGravado"));
    clGenero.setCellValueFactory(new PropertyValueFactory<DiscoTabela, String>("genero"));

    tbvDiscos.setItems(listDiscoTabela);
}


public void listarGeneroTreeView(){

    rootNode.setExpanded(true);

    if(!listGeneroTabela.isEmpty()){
        listGeneroTabela.clear();
        System.out.print("Limpou tabela GeneroTabela");
    }

    for(Genero genero: generoList){         
        try{
            GeneroTabela g = new GeneroTabela(genero.getID(), genero.getGenero());
            listGeneroTabela.add(g.getGenero());
        }catch(Exception e){
            e.printStackTrace();
        }
    }

    for(String genero: listGeneroTabela){
        TreeItem<String> generoLeaf = new TreeItem<>(genero, insertIcon(genero, rootIcon));
        rootNode.getChildren().add(generoLeaf);
    }
    Alert alert = new Alert(AlertType.INFORMATION);
    alert.setContentText(rootNode.getChildren().toString());
    alert.showAndWait();

    tvGenero = new TreeView<String>(rootNode);
    tvGenero.setShowRoot(true);
    tvGenero.setEditable(false);

}

private Node insertIcon(String T, Node rootIcon){

    String imagePath = "/icones/music folders/"+T+"/PNG/"+T+" 1.png";
    Alert alert = new Alert(AlertType.INFORMATION);

    rootIcon = new ImageView(
                new Image(getClass().getResourceAsStream(imagePath)));

    alert.setGraphic(rootIcon);
    alert.showAndWait();

    return rootIcon;
}

private void showGeneroDetails(Genero genero){
    if(genero != null){

    }
}

}