* java.util.stream.Stream#filter}. This method is not being deprecated, but we gently encourage
   * you to migrate to streams.
   */
  // TODO(kevinb): how to omit that last sentence when building GWT javadoc?
  public static <E extends @Nullable Object> Set<E> filter(
      Set<E> unfiltered, Predicate<? super E> predicate) {
    if (unfiltered instanceof SortedSet) {
      return filter((SortedSet<E>) unfiltered, predicate);

   * underlying multimap.
   *
   * <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
   * key/value mapping in the underlying multimap and determine which satisfy the filter. When a

   * underlying multimap.
   *
   * <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
   * key/value mapping in the underlying multimap and determine which satisfy the filter. When a

        "tokenizer" : "fess_japanese_normal",
        "filter" : ["reading_form"]
      },
      "reading_term_analyzer" : {
        "type" : "custom",
        "tokenizer" : "fess_japanese_normal"
      },
      "normalize_analyzer" : {
        "type" : "custom",
        "tokenizer" : "keyword",
        "char_filter" : ["mapping_char"],
        "filter" : ["lowercase"]
      },
      "contents_analyzer" : {

        // TODO always returns empty list
        return split(getIndexAdminArrayFields(), ",").get(stream -> stream.filter(StringUtil::isNotBlank)
                .map(String::trim)
                .filter(s -> isNonEmptyValue(source.get(s)))
                .filter(s -> false) // TODO
                .collect(Collectors.toList()));
    }

    String getIndexAdminDateFields();

	hasTags := len(r.Flags.Filter.Tags) != 0
	isMetadata := len(r.Flags.Filter.Metadata) != 0
	isStorageClassOnly := len(r.Flags.Filter.Metadata) == 1 && strings.EqualFold(r.Flags.Filter.Metadata[0].Key, xhttp.AmzStorageClass)

	skip := func(oi ObjectInfo) (ok bool) {
		if r.Flags.Filter.OlderThan > 0 && time.Since(oi.ModTime) < r.Flags.Filter.OlderThan.D() {

        "tokenizer" : "fess_japanese_normal",
        "filter" : ["reading_form"]
      },
      "reading_term_analyzer" : {
        "type" : "custom",
        "tokenizer" : "fess_japanese_normal"
      },
      "normalize_analyzer" : {
        "type" : "custom",
        "tokenizer" : "keyword",
        "char_filter" : ["mapping_char"],
        "filter" : ["lowercase"]
      },
      "contents_analyzer" : {

        "tokenizer" : "fess_japanese_normal",
        "filter" : ["reading_form"]
      },
      "reading_term_analyzer" : {
        "type" : "custom",
        "tokenizer" : "fess_japanese_normal"
      },
      "normalize_analyzer" : {
        "type" : "custom",
        "tokenizer" : "keyword",
        "char_filter" : ["mapping_char"],
        "filter" : ["lowercase"]
      },
      "contents_analyzer" : {

     * Escapes special characters in an LDAP search filter to prevent injection attacks.
     *
     * @param filter the LDAP search filter to escape
     * @return the escaped filter string
     */
    protected String escapeLDAPSearchFilter(String filter) {
        final StringBuilder sb = new StringBuilder();
        for (int i = 0; i < filter.length(); i++) {
            char curChar = filter.charAt(i);
            switch (curChar) {

        assertQueryContext(
                "{\"function_score\":{\"query\":{\"prefix\":{\"site\":{\"value\":\"fess.codelibs.org\",\"boost\":1.0}}},\"functions\":[{\"filter\":{\"match_all\":{\"boost\":1.0}},\"field_value_factor\":{\"field\":\"boost\",\"factor\":1.0,\"modifier\":\"none\"}}],\"score_mode\":\"multiply\",\"max_boost\":3.4028235E38,\"boost\":1.0}}",
                Map.of("site", List.of("fess.codelibs.org*")), //
                Set.of("fess.codelibs.org"), //