@Override
    public void initialize(URL arg0, ResourceBundle arg1) {
        ConnectionPool.getConnection();

        colItemName.setCellValueFactory(
                new PropertyValueFactory<ItemSaleModel, String>("itemName"));
        colPrice.setCellValueFactory(
                new PropertyValueFactory<ItemSaleModel, String>("price"));
        colQuantity.setCellValueFactory(
                new PropertyValueFactory<ItemSaleModel, String>("quantity"));
        colAmount.setCellValueFactory(
                new PropertyValueFactory<ItemSaleModel, String>("amount"));

        initQuantity();
        txtBarCode.requestFocus();
        lblTotalAmount.textProperty().bind(totalAmountProperty);
        table.getItems().addListener(new ListChangeListener<ItemSaleModel>() {

            @Override
            public void onChanged(javafx.collections.ListChangeListener.Change<? extends ItemSaleModel> arg0) {
                btnRegister.setDisable(table.getItems().isEmpty());
                btnCancel.setDisable(table.getItems().isEmpty());
            }
        });

        table.getItems().clear();
        hideChange();
        countCustomers();
        updateItemCounter(0);
    }