* Iterator#remove} operations. This utility takes the brute-force approach of trying <i>all</i>
 * possible sequences of these operations, up to a given number of steps. So, if the caller
 * specifies to use <i>n</i> steps, a total of <i>3^n</i> tests are actually performed.
 *
 * <p>For instance, if <i>steps</i> is 5, one example sequence that will be tested is:
 *
 * <ol>
 *   <li>remove();

                    if (maxDepth == -1 || crawlRequest.getDepth() < maxDepth) {
                        e.getChildUrlList()
                                .stream() //
                                .filter(data -> !processedUrls.contains(data.getUrl())) //
                                .map(data -> new CrawlRequest(data.getUrl(), crawlRequest.getDepth() + 1)) //
                                .forEach(requestQueue::offer);

    Iterator<String> filtered = filter(unfiltered, equalTo("foo"));
    List<String> expected = singletonList("foo");
    List<String> actual = Lists.newArrayList(filtered);
    assertEquals(expected, actual);
  }

  public void testFilterNoMatch() {
    Iterator<String> unfiltered = Lists.newArrayList("foo", "bar").iterator();
    Iterator<String> filtered = filter(unfiltered, Predicates.alwaysFalse());

            authScheme = new DigestScheme();
        } else if (Constants.NTLM.equals(scheme)) {
            final Properties props = new Properties();
            paramMap.entrySet().stream().filter(e -> e.getKey().startsWith("jcifs.")).forEach(e -> {
                props.setProperty(e.getKey(), e.getValue());
            });
            authScheme = new NTLMScheme(new JcifsEngine(props));

        assertEquals(0, pluginFiles.length);
    }

    public void test_getPluginJarFiles_withFilter() {
        FilenameFilter filter = (dir, name) -> name.endsWith(".jar");
        File[] pluginFiles = ResourceUtil.getPluginJarFiles(filter);
        assertNotNull(pluginFiles);
        // Should return empty array when plugin directory doesn't exist
        assertEquals(0, pluginFiles.length);
    }

     * @return the protected words file if found
     */
    public OptionalEntity<ProtwordsFile> getProtwordsFile(final String dictId) {
        return dictionaryManager.getDictionaryFile(dictId)
                .filter(ProtwordsFile.class::isInstance)
                .map(file -> OptionalEntity.of((ProtwordsFile) file))
                .orElse(OptionalEntity.empty());
    }

    /**
     * Gets a specific protected words item by ID.

 *
 * Implementations authenticate by returning a follow-up request that includes an authorization
 * header, or they may decline the challenge by returning null. In this case the unauthenticated
 * response will be returned to the caller that triggered it.
 *
 * Implementations should check if the initial request already included an attempt to
 * authenticate. If so it is likely that further attempts will not be useful and the authenticator
 * should give up.

        final String name = fessConfig.getQueryBrowserLangParameterName();
        if (StringUtil.isNotBlank(name)) {
            try {
                return requestManager.getParameter(name).filter(StringUtil::isNotBlank).map(LocaleUtils::toLocale);
            } catch (final Exception e) {
                logger.debug("Failed to parse a value of {}.", name, e);
            }
        }

//
// `filterByLabels` is a map of label names to list of allowed label values to
// filter by. Note that this filtering happens before any renaming of labels.
//
// `renameLabels` is a map of label names to rename. The keys are the original
// label names and the values are the new label names.
//
// `bucketFilter` is a list of bucket values to filter. If this is non-empty,
// only metrics for the given buckets are added.
//

    public static final String LDAP_INITIAL_CONTEXT_FACTORY = "ldap.initial.context.factory";

    /** LDAP account filter configuration key. */
    public static final String LDAP_ACCOUNT_FILTER = "ldap.account.filter";

    /** LDAP group filter configuration key. */
    public static final String LDAP_GROUP_FILTER = "ldap.group.filter";

    /** LDAP member of attribute configuration key. */