@Override
  public Optional<String> getValidatorContractAddress() {
    return JsonUtil.getString(bftConfigRoot, VALIDATOR_CONTRACT_ADDRESS).map(String::toLowerCase);
  }
Instantiates a new Json QBFT config options.

@param bftConfigRoot the bft config root
config/src/main/java/org/hyperledger/besu/config/JsonQbftConfigOptions.java