private StoreKeyConverter createAndSetupMockStoreKeyConverter(MockStoreKeyConverterFactory factory,
      Pair<String, String>[] pairs) throws Exception {
    Map<StoreKey, StoreKey> map = new HashMap<>();
    for (Pair<String, String> pair : pairs) {
      map.put(createBlobId(pair.getFirst()), createBlobId(pair.getSecond()));
    }
    factory.setConversionMap(map);
    return factory.getStoreKeyConverter();
  }
Tests using the transformer with Message inputs that have null components
@throws Exception
ambry-replication/src/test/java/com/github/ambry/replication/BlobIdTransformerTest.java