final String[] tags = extractTags(tagFieldNames, tagFieldName -> {
            final List<String> results = new ArrayList<>(Arrays.asList(SuggestUtil.parseQuery(queryString, tagFieldName)));
            if (filterQueryString != null) {
                results.addAll(Arrays.asList(SuggestUtil.parseQuery(filterQueryString, tagFieldName)));
            }
            return results.toArray(new String[0]);
        });

        /** Supported fields key. */
        public static final String SUPPORTED_FIELDS = "supportedFields";
        /** Tag field name key. */
        public static final String TAG_FIELD_NAME = "tagFieldName";
        /** Role field name key. */
        public static final String ROLE_FIELD_NAME = "roleFieldName";
        /** Language field name key. */
        public static final String LANG_FIELD_NAME = "langFieldName";