new ImmutableTable.Builder<String, SecretKey, HashFunction>()
          .put("HmacMD5", MD5_KEY, Hashing.hmacMd5(MD5_KEY))
          .put("HmacSHA1", SHA1_KEY, Hashing.hmacSha1(SHA1_KEY))
          .put("HmacSHA256", SHA256_KEY, Hashing.hmacSha256(SHA256_KEY))
          .put("HmacSHA512", SHA512_KEY, Hashing.hmacSha512(SHA512_KEY))
          .build();

  public void testNulls() {

      new ImmutableTable.Builder<String, SecretKey, HashFunction>()
          .put("HmacMD5", MD5_KEY, Hashing.hmacMd5(MD5_KEY))
          .put("HmacSHA1", SHA1_KEY, Hashing.hmacSha1(SHA1_KEY))
          .put("HmacSHA256", SHA256_KEY, Hashing.hmacSha256(SHA256_KEY))
          .put("HmacSHA512", SHA512_KEY, Hashing.hmacSha512(SHA512_KEY))
          .build();

  public void testNulls() {

  }

  public void testSha1() {
    HashTestUtils.checkAvalanche(Hashing.sha1(), 100, 0.4);
    HashTestUtils.checkNo2BitCharacteristics(Hashing.sha1());
    HashTestUtils.checkNoFunnels(Hashing.sha1());
    HashTestUtils.assertInvariants(Hashing.sha1());
    assertEquals("Hashing.sha1()", Hashing.sha1().toString());
  }

  public void testSha256() {

  public void testHashCode_equalsAndSerializable() throws Exception {
    sanityTester().testEqualsAndSerializable();
  }

  public void testRoundTripHashCodeUsingBaseEncoding() {
    HashCode hash1 = Hashing.sha1().hashString("foo", Charsets.US_ASCII);
    HashCode hash2 = HashCode.fromBytes(BaseEncoding.base16().lowerCase().decode(hash1.toString()));
    assertEquals(hash1, hash2);
  }

  public void testObjectHashCode() {

  public void testHashCode_equalsAndSerializable() throws Exception {
    sanityTester().testEqualsAndSerializable();
  }

  public void testRoundTripHashCodeUsingBaseEncoding() {
    HashCode hash1 = Hashing.sha1().hashString("foo", Charsets.US_ASCII);
    HashCode hash2 = HashCode.fromBytes(BaseEncoding.base16().lowerCase().decode(hash1.toString()));
    assertEquals(hash1, hash2);
  }

  public void testObjectHashCode() {

   */
  @Deprecated
  public static HashFunction sha1() {
    return Sha1Holder.SHA_1;
  }

  private static class Sha1Holder {
    static final HashFunction SHA_1 = new MessageDigestHashFunction("SHA-1", "Hashing.sha1()");
  }

  /** Returns a hash function implementing the SHA-256 algorithm (256 hash bits). */
  public static HashFunction sha256() {
    return Sha256Holder.SHA_256;
  }

  }

  public void testSha1() {
    HashTestUtils.checkAvalanche(Hashing.sha1(), 100, 0.4);
    HashTestUtils.checkNo2BitCharacteristics(Hashing.sha1());
    HashTestUtils.checkNoFunnels(Hashing.sha1());
    HashTestUtils.assertInvariants(Hashing.sha1());
    assertEquals("Hashing.sha1()", Hashing.sha1().toString());
  }

  public void testSha256() {

 *       byte sequences under the covers.
 *   <li><b>hash code:</b> each hash function always yields hash codes of the same fixed bit length
 *       (given by {@link #bits}). For example, {@link Hashing#sha1} produces a 160-bit number,
 *       while {@link Hashing#murmur3_32()} yields only 32 bits. Because a {@code long} value is
 *       clearly insufficient to hold all hash code values, this API represents a hash code as an