public void focusLost(FocusEvent e) {
        Object src = e.getSource();
        if (src == null)
            return;
        if (src == currentPageNumberTextField) {
            String fieldValue = currentPageNumberTextField.getText();
            String modelValue = Integer.toString(documentViewController.getCurrentPageDisplayValue());
            if (!fieldValue.equals(modelValue))
                currentPageNumberTextField.setText(modelValue);
        }
    }