public static String getGFInstanceURN() throws RegistrationException {
SysnetRegistrationService srs = new SysnetRegistrationService(getServiceTagRegistry());
List<ServiceTag> st = srs.getRegistrationDescriptors(getGFProductURN());
if (st.isEmpty()) {
throw new RegistrationException("Instance URN for " +
getGFProductURN() + " not found"); // i18n
}
return st.get(0).getInstanceURN();
}