@Override
 public Wsdl getWsdl(String externalId) {
   List<Wsdl> matches = wsdlRepository.findAnyByExternalId(externalId);
   if (matches.size() > 1) {
     throw new IllegalStateException("multiple matches found to " + externalId + ": " + matches);
   } else if (matches.size() == 1) {
     return matches.iterator().next();
   } else {
     return null;
   }
 }