// [x509_extensions]
    // subjectAltName=DNS:localhost.localdomain,DNS:localhost,IP:127.0.0.1
    //
    // $ openssl req -x509 -nodes -days 36500 -subj '/CN=localhost' -config ./cert.cnf \
    //     -newkey rsa:512 -out cert.pem
    val certificate =
      certificate(
        """
        -----BEGIN CERTIFICATE-----
        MIIBWDCCAQKgAwIBAgIJANS1EtICX2AZMA0GCSqGSIb3DQEBBQUAMBQxEjAQBgNV

  fun decodeRsa512() {
    // The certificate + private key below was generated with OpenSSL. Never generate certificates
    // with MD5 or 512-bit RSA; that's insecure!
    //
    // openssl req \
    //   -x509 \
    //   -md5 \
    //   -nodes \
    //   -days 1 \
    //   -newkey rsa:512 \
    //   -keyout privateKey.key \
    //   -out certificate.crt
    val certificatePem =
      """

  }

  /** Returns a hash function implementing the SHA-512 algorithm (512 hash bits). */
  public static HashFunction sha512() {
    return Sha512Holder.SHA_512;
  }

  private static final class Sha512Holder {
    static final HashFunction SHA_512 =
        new MessageDigestHashFunction("SHA-512", "Hashing.sha512()");
  }

  /**

  }

  /** Returns a hash function implementing the SHA-512 algorithm (512 hash bits). */
  public static HashFunction sha512() {
    return Sha512Holder.SHA_512;
  }

  private static final class Sha512Holder {
    static final HashFunction SHA_512 =
        new MessageDigestHashFunction("SHA-512", "Hashing.sha512()");
  }

  /**

    CacheBuilder<Object, Object> builder =
        CacheBuilder.newBuilder().initialCapacity(512).maximumSize(Long.MAX_VALUE);
    LocalCache<?, ?> cache = ((LocalCache.LocalManualCache<?, ?>) builder.build()).localCache;
    assertThat(cache.segments.length * cache.segments[0].table.length()).isEqualTo(512);
  }

  @GwtIncompatible // maximumWeight
  public void testMaximumWeight_negative() {

    CacheBuilder<Object, Object> builder =
        CacheBuilder.newBuilder().initialCapacity(512).maximumSize(Long.MAX_VALUE);
    LocalCache<?, ?> cache = ((LocalCache.LocalManualCache<?, ?>) builder.build()).localCache;
    assertThat(cache.segments.length * cache.segments[0].table.length()).isEqualTo(512);
  }

  @GwtIncompatible // maximumWeight
  public void testMaximumWeight_negative() {

    assertHashBytesThrowsCorrectExceptions(hashFunction);
    assertIndependentHashers(hashFunction);
    assertShortcutsAreEquivalent(hashFunction, 512);
  }

  static void assertHashByteBufferInvariants(HashFunction hashFunction) {
    assertHashByteBufferMatchesBytes(hashFunction);
    assertHashByteBufferExhaustsBuffer(hashFunction);

  }

  /** Create a sufficiently large header set to overflow INITIAL_MAX_FRAME_SIZE bytes.  */
  private fun largeHeaders(): List<Header> {
    val nameValues = arrayOfNulls<String>(32)
    val chars = CharArray(512)
    var i = 0
    while (i < nameValues.size) {
      Arrays.fill(chars, i.toChar())
      val string = String(chars)
      nameValues[i++] = string
      nameValues[i++] = string
    }