return "lang";
                case FessConfig.INDEX_FIELD_has_cache:
                    return "has_cache";
                case FessConfig.INDEX_FIELD_last_modified:
                    return "last_modified";
                case FessConfig.INDEX_FIELD_ANCHOR:
                    return "anchor";
                case FessConfig.INDEX_FIELD_SEGMENT:
                    return "segment";

            public String getIndexFieldSite() {
                return "site";
            }

            @Override
            public String getIndexFieldLastModified() {
                return "last_modified";
            }

            @Override
            public String getIndexFieldTimestamp() {
                return "timestamp";
            }

            @Override

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

            public String getIndexFieldHost() {
                return "host";
            }

            @Override
            public String getIndexFieldLastModified() {
                return "last_modified";
            }

            @Override
            public String getIndexFieldMimetype() {
                return "mimetype";
            }

            @Override

            final Date lastModified = FessFunctions.parseDate(lastModifiedObj.toString());
            if (lastModified != null) {
                return lastModified;
            }
        } else if (lastModifiedObj instanceof final String[] lastModifieds && lastModifieds.length > 0) {
            final Date lastModified = FessFunctions.parseDate(lastModifieds[0]);
            if (lastModified != null) {

            public String getIndexFieldSite() {
                return "site";
            }

            @Override
            public String getIndexFieldLastModified() {
                return "last_modified";
            }

            @Override
            public String getIndexFieldTimestamp() {
                return "timestamp";
            }

            @Override

    /** The key of the configuration. e.g. has_cache */
    String INDEX_FIELD_has_cache = "index.field.has_cache";

    /** The key of the configuration. e.g. last_modified */
    String INDEX_FIELD_last_modified = "index.field.last_modified";

    /** The key of the configuration. e.g. anchor */
    String INDEX_FIELD_ANCHOR = "index.field.anchor";

    /** The key of the configuration. e.g. segment */

# Field name for language in the index.
index.field.lang=lang
# Field name for cache status in the index.
index.field.has_cache=has_cache
# Field name for last modified date in the index.
index.field.last_modified=last_modified
# Field name for anchor in the index.
index.field.anchor=anchor
# Field name for segment in the index.
index.field.segment=segment
# Field name for role in the index.
index.field.role=role

            public String getIndexFieldSite() {
                return "site";
            }

            @Override
            public String getIndexFieldLastModified() {
                return "last_modified";
            }

            @Override
            public String getIndexFieldTimestamp() {
                return "timestamp";
            }

            @Override

                Set.of(), //
                "{\"timestamp\":{\"order\":\"desc\"}}{\"last_modified\":{\"order\":\"asc\"}}", //
                buildQuery("sort:timestamp.desc sort:last_modified"));
        assertQueryContext(query, Map.of(), //
                Set.of(), //
                "{\"timestamp\":{\"order\":\"desc\"}}{\"last_modified\":{\"order\":\"desc\"}}", //
                buildQuery("sort:timestamp.desc sort:last_modified.desc"));