class DefaultBlockchain implements MutableBlockchain {

  @Override
  public boolean removeObserver(final long observerId) {
    return blockAddedObservers.unsubscribe(observerId);
  }

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

}