import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;

public class SpeedMain {
  private static MessageDigest md;
  private static final int size = 1_000_000;
  private static final int pathSize = 200;

  public static void main(String[] args) throws NoSuchAlgorithmException {
    md = MessageDigest.getInstance("SHA-256");
    StringBuilder path = new StringBuilder();
    Random random = new Random();

    for (int i = 0; i < pathSize; i++) {
      path.append(random.nextInt(9));
    }

    long curTime = System.nanoTime();

    for(int i = 0; i < size; i++){
      cal(path.toString());
      md.reset();
    }

    long finishTime = System.nanoTime();
    System.out.println("Throughput: " + size / ((finishTime - curTime) / 1_000_000) + " num / ms.");

  }

  private static byte[] cal(String s){
    return md.digest(s.getBytes());
  }
}