class DefaultBlockchain implements MutableBlockchain {

  @VisibleForTesting
  Set<Hash> getForks() {
    return new HashSet<>(blockchainStorage.getForkHeads());
  }

  private  DefaultBlockchain(
      final Optional<Block> genesisBlock,
      final BlockchainStorage blockchainStorage,
      final MetricsSystem metricsSystem,
      final long reorgLoggingThreshold);

}