try {
      return MessageDigest.getInstance(algorithmName);
    } catch (NoSuchAlgorithmException e) {
      throw new AssertionError(e);
    }
  }

  @Override
  public Hasher newHasher() {
    if (supportsClone) {
      try {
        return new MessageDigestHasher((MessageDigest) prototype.clone(), bytes);
      } catch (CloneNotSupportedException e) {
        // falls through
      }
    }

    try {
      return MessageDigest.getInstance(algorithmName);
    } catch (NoSuchAlgorithmException e) {
      throw new AssertionError(e);
    }
  }

  @Override
  public Hasher newHasher() {
    if (supportsClone) {
      try {
        return new MessageDigestHasher((MessageDigest) prototype.clone(), bytes);
      } catch (CloneNotSupportedException e) {
        // falls through
      }
    }

  private final int seed;

  Murmur3_128HashFunction(int seed) {
    this.seed = seed;
  }

  @Override
  public int bits() {
    return 128;
  }

  @Override
  public Hasher newHasher() {
    return new Murmur3_128Hasher(seed);
  }

  @Override
  public String toString() {
    return "Hashing.murmur3_128(" + seed + ")";
  }

  @Override

    this.c = c;
    this.d = d;
    this.k0 = k0;
    this.k1 = k1;
  }

  @Override
  public int bits() {
    return 64;
  }

  @Override
  public Hasher newHasher() {
    return new SipHasher(c, d, k0, k1);
  }

  // TODO(kak): Implement and benchmark the hashFoo() shortcuts.

  @Override
  public String toString() {

    assertEquals(
        String.format("expected: %08x, actual: %08x", expectedCrc, actualCrc),
        expectedCrc,
        actualCrc);
    int actualCrcHasher = Hashing.crc32c().newHasher().putBytes(data).hash().asInt();
    assertEquals(
        String.format("expected: %08x, actual: %08x", expectedCrc, actualCrc),
        expectedCrc,
        actualCrcHasher);
  }

          // passes, and there is still a little endianness bug lurking around.
        }
      }

      Control control = new Control();
      Hasher controlSink = control.newHasher(1024);

      Iterable<Hasher> sinksAndControl =
          Iterables.concat(sinks, Collections.singleton(controlSink));
      for (int insertion = 0; insertion < totalInsertions; insertion++) {

    File asciiFile = getTestFile("ascii.txt");
    File i18nFile = getTestFile("i18n.txt");

    String init = "d41d8cd98f00b204e9800998ecf8427e";
    assertEquals(init, Hashing.md5().newHasher().hash().toString());

    String asciiHash = "e5df5a39f2b8cb71b24e1d8038f93131";
    assertEquals(asciiHash, Files.hash(asciiFile, Hashing.md5()).toString());

    String i18nHash = "7fa826962ce2079c8334cd4ebf33aea4";

final class Crc32cHashFunction extends AbstractHashFunction {
  static final HashFunction CRC_32_C = new Crc32cHashFunction();

  @Override
  public int bits() {
    return 32;
  }

  @Override
  public Hasher newHasher() {
    return new Crc32cHasher();
  }

  @Override
  public String toString() {
    return "Hashing.crc32c()";
  }

  static final class Crc32cHasher extends AbstractStreamingHasher {

    /*

    File asciiFile = getTestFile("ascii.txt");
    File i18nFile = getTestFile("i18n.txt");

    String init = "d41d8cd98f00b204e9800998ecf8427e";
    assertEquals(init, Hashing.md5().newHasher().hash().toString());

    String asciiHash = "e5df5a39f2b8cb71b24e1d8038f93131";
    assertEquals(asciiHash, Files.hash(asciiFile, Hashing.md5()).toString());

    String i18nHash = "7fa826962ce2079c8334cd4ebf33aea4";

   *
   * @throws IOException if an I/O error occurs while reading from this source
   */
  public HashCode hash(HashFunction hashFunction) throws IOException {
    Hasher hasher = hashFunction.newHasher();
    copyTo(Funnels.asOutputStream(hasher));
    return hasher.hash();
  }

  /**
   * Checks that the contents of this byte source are equal to the contents of the given byte
   * source.
   *