* Removes protocol and path components to return just the hostname.
     *
     * @param u the URL string to extract host from
     * @return the host name, or empty string if URL is blank, or unknown hostname if parsing fails
     */
    default String getHost(final String u) {
        if (StringUtil.isBlank(u)) {
            return StringUtil.EMPTY; // empty
        }

        String url = u;

        queryContext = new QueryContext("", false);
        assertEquals("*", queryContext.getQueryString());
        assertNull(queryContext.getDefaultField());
    }

    // Test constructor with blank query string
    @Test
    public void test_constructor_blankQueryString() {
        queryContext = new QueryContext("   ", false);
        assertEquals("*", queryContext.getQueryString());

                         * blank password initializes signing.
                         */
                        if (transport.isSignatureSetupRequired(auth)) {
                            if (auth.hashesExternal && NtlmPasswordAuthentication.DEFAULT_PASSWORD != NtlmPasswordAuthentication.BLANK) {
                                /* preauthentication
                                 */

        }

        final WebAuthenticationConfig config = new WebAuthenticationConfig();

        // host/port/realm: only set if not blank (null means "any" - AuthScope.ANY equivalent)
        final String host = paramMap.get(prefix + "host");
        if (StringUtil.isNotBlank(host)) {
            config.setHost(host);
        }

        assertTrue(user.getEnvironment().isEmpty());
    }

    @Test
    public void test_getPermissions_withoutLdapConfig() {
        // Test when baseDn or accountFilter is blank
        ComponentUtil.setFessConfig(new FessConfig.SimpleImpl() {
            @Override
            public String getLdapBaseDn() {
                return "";
            }

            @Override

  private static final long NEXT_MASK = (1L << 32) - 1;

  /** Bitmask that selects the high 32 bits. */
  private static final long HASH_MASK = ~NEXT_MASK;

  static final int DEFAULT_SIZE = 3;

  // used to indicate blank table entries
  static final int UNSET = -1;

  /*
   * The array fields below are not initialized directly in the constructor, but they're initialized
   * by init(), which the constructor calls.
   */

        final String url = urlQueue.getUrl();
        if (StringUtil.isBlank(url)) {
            if (logger.isDebugEnabled()) {
                logger.debug("URL is a blank: {}", url);
            }
            return false;
        }

        final String sessionId = urlQueue.getSessionId();
        if (super.exists(sessionId, url)) {
            return true;
        }

        docMap.put("_id", "nonexistent");

        File result = thumbnailManager.getThumbnailFile(docMap);
        assertNull(result);
    }

    // Test getThumbnailFile with blank path
    @Test
    public void test_getThumbnailFile_blankPath() {
        Map<String, Object> docMap = new HashMap<>();
        // No _id field, so docid will be null

      for (String keyValuePair : KEYS_SPLITTER.split(cacheBuilderSpecification)) {
        List<String> keyAndValue = ImmutableList.copyOf(KEY_VALUE_SPLITTER.split(keyValuePair));
        checkArgument(!keyAndValue.isEmpty(), "blank key-value pair");
        checkArgument(
            keyAndValue.size() <= 2,
            "key-value pair %s with more than one equals sign",
            keyValuePair);

      for (String keyValuePair : KEYS_SPLITTER.split(cacheBuilderSpecification)) {
        List<String> keyAndValue = ImmutableList.copyOf(KEY_VALUE_SPLITTER.split(keyValuePair));
        checkArgument(!keyAndValue.isEmpty(), "blank key-value pair");
        checkArgument(
            keyAndValue.size() <= 2,
            "key-value pair %s with more than one equals sign",
            keyValuePair);