assertNull(MessageDigestUtil.digest("MD5", null));
        assertEquals("ea703e7aa1efda0064eaa507d9e8ab7e", MessageDigestUtil.digest("MD5", text));
        assertEquals("31f30ddbcb1bf8446576f0e64aa4c88a9f055e3c", MessageDigestUtil.digest("SHA-1", text));
        assertEquals("ecb666d778725ec97307044d642bf4d160aabb76f56c0069c71ea25b1e926825", MessageDigestUtil.digest("SHA-256", text));

        try {

        } catch (final UnsupportedEncodingException e) {
            throw new ClIllegalStateException(e);
        }
        final byte[] digest = msgDigest.digest();

        final StringBuilder buffer = new StringBuilder(200);
        for (final byte element : digest) {
            final String tmp = Integer.toHexString(element & 0xff);
            if (tmp.length() == 1) {
                buffer.append('0').append(tmp);

 * token68:
 *
 * ```
 * WWW-Authenticate: Digest foo=bar
 * WWW-Authenticate: Digest foo=
 * ```
 *
 * Similarly, the first line has one challenge and the second line has two challenges:
 *
 * ```
 * WWW-Authenticate: Digest ,foo=bar
 * WWW-Authenticate: Digest ,foo
 * ```
 */
fun Headers.parseChallenges(headerName: String): List<Challenge> {

 * [OkHttp AWS Signer](https://github.com/babbel/okhttp-aws-signer): AWS V4 signing algorithm for OkHttp requests
 * [okhttp-digest](https://github.com/rburgst/okhttp-digest): A digest authenticator for OkHttp.
 * [OkHttp Idling Resource](https://github.com/JakeWharton/okhttp-idling-resource): An Espresso IdlingResource for OkHttp.

    MESSAGE_DIGEST_API() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        MessageDigest md = algorithm.getMessageDigest();
        md.update(input);
        return md.digest();
      }
    },
    HASH_FUNCTION_DIRECT() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        return algorithm.getHashFunction().hashBytes(input).asBytes();
      }
    },

    MESSAGE_DIGEST_API() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        MessageDigest md = algorithm.getMessageDigest();
        md.update(input);
        return md.digest();
      }
    },
    HASH_FUNCTION_DIRECT() {
      @Override
      public byte[] hash(Algorithm algorithm, byte[] input) {
        return algorithm.getHashFunction().hashBytes(input).asBytes();
      }
    },

        // mimetype
        defaultDataMap.put(fessConfig.getIndexFieldMimetype(), mimeType);
        // title
        // content
        // cache
        // digest
        // host
        // site
        // url
        // anchor
        // content_length
        // last_modified
        // id
        // virtual_host

            public static final String DEFAULT_LANG = "default.lang";
            public static final String DEFAULT_CONTENT = "default.content";
            public static final String DEFAULT_DIGEST = "default.digest";
            // xapth.<field>=<value>
        }

        // config.*
        public static class Config {
            public static final String KEEP_ORIGINAL_BODY = "keep.original.body";

    }

    private AuthScheme getAuthScheme() {
        final String scheme = getProtocolScheme();
        if (Constants.BASIC.equals(scheme)) {
            return new BasicScheme();
        }
        if (Constants.DIGEST.equals(scheme)) {
            return new DigestScheme();
        }
        if (Constants.NTLM.equals(scheme)) {
            final Properties props = new Properties();