}

  @Benchmark
  int hasher(int reps) {
    HashFunction hashFunction = hashFunctionEnum.getHashFunction();
    int result = 37;
    for (int i = 0; i < reps; i++) {
      result ^= hashFunction.newHasher().putBytes(testBytes).hash().asBytes()[0];
    }
    return result;
  }

  @Benchmark
  int hashFunction(int reps) {
    HashFunction hashFunction = hashFunctionEnum.getHashFunction();
    int result = 37;

      result = (byte) (result ^ checksum.asLong());
    }
    return result;
  }

  // Helpers + main

  private byte runHashFunction(int reps, HashFunction hashFunction) {
    byte result = 0x01;
    // Trick the JVM to prevent it from using the hash function non-polymorphically
    result ^= Hashing.crc32().hashInt(reps).asBytes()[0];

  private Hasher hasher;
  private HashFunction hashFunction;
  private final ByteArrayOutputStream buffer = new ByteArrayOutputStream();

  @SuppressWarnings("DoNotMock")
  @Override
  protected void setUp() throws Exception {
    super.setUp();
    hasher = mock(Hasher.class);
    hashFunction = mock(HashFunction.class);

    when(hashFunction.newHasher()).thenReturn(hasher);
  }

  private Hasher hasher;
  private HashFunction hashFunction;
  private static final byte[] testBytes = new byte[] {'y', 'a', 'm', 's'};
  private ByteArrayInputStream buffer;

  @SuppressWarnings("DoNotMock")
  @Override
  protected void setUp() throws Exception {
    super.setUp();
    hasher = mock(Hasher.class);
    hashFunction = mock(HashFunction.class);
    buffer = new ByteArrayInputStream(testBytes);

  private Hasher hasher;
  private HashFunction hashFunction;
  private static final byte[] testBytes = new byte[] {'y', 'a', 'm', 's'};
  private ByteArrayInputStream buffer;

  @SuppressWarnings("DoNotMock")
  @Override
  protected void setUp() throws Exception {
    super.setUp();
    hasher = mock(Hasher.class);
    hashFunction = mock(HashFunction.class);
    buffer = new ByteArrayInputStream(testBytes);

  // These can probably be removed sooner or later.
  ;

  private final HashFunction hashFunction;

  private HashFunctionEnum(HashFunction hashFunction) {
    this.hashFunction = hashFunction;
  }

  HashFunction getHashFunction() {
    return hashFunction;
  }

    SHA_256("SHA-256", Hashing.sha256()),
    SHA_384("SHA-384", Hashing.sha384()),
    SHA_512("SHA-512", Hashing.sha512());

    private final String algorithmName;
    private final HashFunction hashFn;

    Algorithm(String algorithmName, HashFunction hashFn) {
      this.algorithmName = algorithmName;
      this.hashFn = hashFn;
    }

    public MessageDigest getMessageDigest() {
      try {

    SHA_256("SHA-256", Hashing.sha256()),
    SHA_384("SHA-384", Hashing.sha384()),
    SHA_512("SHA-512", Hashing.sha512());

    private final String algorithmName;
    private final HashFunction hashFn;

    Algorithm(String algorithmName, HashFunction hashFn) {
      this.algorithmName = algorithmName;
      this.hashFn = hashFn;
    }

    public MessageDigest getMessageDigest() {
      try {

      result = (byte) (result ^ checksum.asLong());
    }
    return result;
  }

  // Helpers + main

  private byte runHashFunction(int reps, HashFunction hashFunction) {
    byte result = 0x01;
    // Trick the JVM to prevent it from using the hash function non-polymorphically
    result ^= Hashing.crc32().hashInt(reps).asBytes()[0];

  // be (optionally) be combined with another if needed (with something like
  // MultiplexingOutputStream).
  public HashingOutputStream(HashFunction hashFunction, OutputStream out) {
    super(checkNotNull(out));
    this.hasher = checkNotNull(hashFunction.newHasher());
  }

  @Override
  public void write(int b) throws IOException {
    hasher.putByte((byte) b);
    out.write(b);
  }

  @Override