@Override
 public Optional<KnownIdentities> findByIdentity(IdentityType type, String identityValue) {
   for (Map.Entry<Long, KnownIdentities> aggregate : aggregateMap.entrySet()) {
     for (Identity identity : aggregate.getValue().getKnownIdentities()) {
       if (identity.getType().equals(type) && identity.getIdentifier().equals(identityValue)) {
         return Optional.of(aggregate.getValue());
       }
     }
   }
   return Optional.empty();
 }