@Override
  public DescriptorDigest deserialize(JsonParser jsonParser, DeserializationContext ignored)
      throws IOException {
    try {
      return DescriptorDigest.fromDigest(jsonParser.getValueAsString());
    } catch (DigestException ex) {
      throw new IOException(ex);
    }
  }
Deserializes a JSON element into a {@link DescriptorDigest} object.
jib-core/src/main/java/com/google/cloud/tools/jib/image/json/DescriptorDigestDeserializer.java