Griffon/JavaFX - Adding a change listener to a text field Part 1

gistfile1.groovy

import javafx.beans.value.ChangeListener
import javafx.beans.value.ObservableValue
import org.apache.commons.lang.StringUtils

// model
@FXBindable String amount1

// view
textField(id: 'amount1', text: bind(model.amount1Property))

noparent {
    amount1.textProperty().addListener(new ChangeListener<String>() {
        @Override
        public void changed(ObservableValue<? extends String> observable,
                            String oldValue, String newValue) {
            try {
                if (StringUtils.isNotBlank(newValue)) {
                    Integer.parseInt(newValue);
                }
            } catch (Exception e) {
                observable.setValue(oldValue);
            }
        }
    });
}