public DefaultIvyExtraInfoSpec() {
        super();
    }

    @Override
    public void add(String namespace, String name, String value) {
        if (XmlValidation.isValidXmlName(name)) {
            extraInfo.put(new NamespaceId(namespace, name), value);
        } else {
            throw new IllegalArgumentException(String.format("Invalid ivy extra info element name: '%s'", name));
        }