* and checks that their results are identical, no matter which newHasher version we used.
   */
  public void testExhaustive() {
    List<Hasher> hashers =
        ImmutableList.of(
            new StreamingVersion().newHasher(),
            new StreamingVersion().newHasher(52),
            new NonStreamingVersion().newHasher(),
            new NonStreamingVersion().newHasher(123));
    Random random = new Random(0);

    hasher = HASH_FN.newHasher();
    hasher
        .putChar((char) 0x0101)
        .putChar((char) 0x0100)
        .putChar((char) 0x0000)
        .putChar((char) 0x0000);
    assertEquals(hashCode, hasher.hash().asLong());

    hasher = HASH_FN.newHasher();
    hasher.putBytes(new byte[] {0x01, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00});
    assertEquals(hashCode, hasher.hash().asLong());

    hasher = HASH_FN.newHasher();
    hasher
        .putChar((char) 0x0101)
        .putChar((char) 0x0100)
        .putChar((char) 0x0000)
        .putChar((char) 0x0000);
    assertEquals(hashCode, hasher.hash().asLong());

    hasher = HASH_FN.newHasher();
    hasher.putBytes(new byte[] {0x01, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00});
    assertEquals(hashCode, hasher.hash().asLong());

    int res = 0;
    for (int i = 0; i < reps; i++) {
      res +=
          System.identityHashCode(
              hashFunctionEnum
                  .getHashFunction()
                  .newHasher()
                  .putString(strings[i & SAMPLE_MASK], UTF_8)
                  .hash());
    }
    return res;
  }

  @Benchmark
  int hashUtf8GetBytes(int reps) {
    int res = 0;

    buffer = new ByteArrayInputStream(testBytes);

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

  public void testRead_putSingleByte() throws Exception {
    HashingInputStream in = new HashingInputStream(hashFunction, buffer);

    int b = in.read();
    assertEquals('y', b);

    verify(hasher).putByte((byte) 'y');
    verify(hashFunction).newHasher();
    verifyNoMoreInteractions(hashFunction, hasher);
  }

  /* protected */ abstract HashCode makeHash(Hasher[] hashers);

  @Override
  public Hasher newHasher() {
    Hasher[] hashers = new Hasher[functions.length];
    for (int i = 0; i < hashers.length; i++) {
      hashers[i] = functions[i].newHasher();
    }
    return fromHashers(hashers);
  }

  @Override
  public Hasher newHasher(int expectedInputSize) {
    checkArgument(expectedInputSize >= 0);

 * the hash computation done using {@linkplain #newHasher()} are delegated to the {@linkplain
 * #hashBytes(byte[], int, int)} method.
 *
 * @author Dimitris Andreou
 */
@Immutable
abstract class AbstractNonStreamingHashFunction extends AbstractHashFunction {
  @Override
  public Hasher newHasher() {
    return newHasher(32);
  }

  @Override
  public Hasher newHasher(int expectedInputSize) {

  }

  @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;

      }
    },
    HASH_FUNCTION_VIA_HASHER() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        return algorithm.getHashFunction().newHasher().putBytes(input).hash().asBytes();
      }
    };
    ;

    abstract byte[] hash(Algorithm algorithm, byte[] input);
  }

  private enum Algorithm {
    MD5("MD5", Hashing.md5()),

      }
    },
    HASH_FUNCTION_VIA_HASHER() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        return algorithm.getHashFunction().newHasher().putBytes(input).hash().asBytes();
      }
    };
    ;

    abstract byte[] hash(Algorithm algorithm, byte[] input);
  }

  private enum Algorithm {
    MD5("MD5", Hashing.md5()),