class AssignmentListItemWidgetViewImpl extends Composite implements AssignmentListItemWidgetView,
                                                                           ComboBoxView.ModelPresenter {

    @Override
    public String getModelValue(final ValueListBox<String> listBox) {
        if (listBox == dataType) {
            String value = getCustomDataType();
            return isEmpty(value) ? getDataType() : value;
        }

        if (listBox == processVar) {
            String value = getExpression();
            return isEmpty(value) ? getProcessVar() : value;
        }

        return EMPTY_VALUE;
    }

}