class DatatypeFactory {

    public Datatype getDatatype(QName qn) throws ValidationException {
        Datatype ret = constructed.get(qn);
        if(ret==null) {
            ret = constructDatatype(qn);
            constructed.put(qn, ret);
        }
        return ret;
    }

    @SuppressWarnings("OverridableMethodCallInConstructor") private  DatatypeFactory(ConversionRules conversionRules);

}