return "_version";
                case FessConfig.INDEX_FIELD_seq_no:
                    return "_seq_no";
                case FessConfig.INDEX_FIELD_primary_term:
                    return "_primary_term";
                case FessConfig.INDEX_FIELD_LANG:
                    return "lang";
                case FessConfig.INDEX_FIELD_has_cache:
                    return "has_cache";

        @Override
        public String getIndexFieldSeqNo() {
            return "_seq_no";
        }

        @Override
        public String getIndexFieldPrimaryTerm() {
            return "_primary_term";
        }

        @Override
        public String getResponseFieldContentTitle() {
            return "title";
        }

        @Override

index.field.id=_id
# Field name for version in the index.
index.field.version=_version
# Field name for sequence number in the index.
index.field.seq_no=_seq_no
# Field name for primary term in the index.
index.field.primary_term=_primary_term
# 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.

    /** The key of the configuration. e.g. _seq_no */
    String INDEX_FIELD_seq_no = "index.field.seq_no";

    /** The key of the configuration. e.g. _primary_term */
    String INDEX_FIELD_primary_term = "index.field.primary_term";

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

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

            esEntity.asDocMeta().seqNo(seqNo);
        }
        final Long primaryTerm = esEntity.asDocMeta().primaryTerm();
        if (primaryTerm != null && primaryTerm.longValue() != SequenceNumbers.UNASSIGNED_PRIMARY_TERM) {
            esEntity.asDocMeta().primaryTerm(primaryTerm);
        }
        return builder;
    }

        }

        public Long seqNo() {
            return seqNo;
        }

        public DocMeta primaryTerm(Long primaryTerm) {
            this.primaryTerm = primaryTerm;
            return this;
        }

        public Long primaryTerm() {
            return primaryTerm;
        }

        public DocMeta indexOption(RequestOptionCall<IndexRequestBuilder> builder) {

            esEntity.asDocMeta().seqNo(seqNo);
        }
        final Long primaryTerm = esEntity.asDocMeta().primaryTerm();
        if (primaryTerm != null && primaryTerm.longValue() != SequenceNumbers.UNASSIGNED_PRIMARY_TERM) {
            esEntity.asDocMeta().primaryTerm(primaryTerm);
        }
        return builder;
    }

        }

        public Long seqNo() {
            return seqNo;
        }

        public DocMeta primaryTerm(Long primaryTerm) {
            this.primaryTerm = primaryTerm;
            return this;
        }

        public Long primaryTerm() {
            return primaryTerm;
        }

        public DocMeta indexOption(RequestOptionCall<IndexRequestBuilder> builder) {

        }

        public Long seqNo() {
            return seqNo;
        }

        public DocMeta primaryTerm(Long primaryTerm) {
            this.primaryTerm = primaryTerm;
            return this;
        }

        public Long primaryTerm() {
            return primaryTerm;
        }

        public DocMeta indexOption(RequestOptionCall<IndexRequestBuilder> builder) {

            esEntity.asDocMeta().seqNo(seqNo);
        }
        final Long primaryTerm = esEntity.asDocMeta().primaryTerm();
        if (primaryTerm != null && primaryTerm.longValue() != SequenceNumbers.UNASSIGNED_PRIMARY_TERM) {
            esEntity.asDocMeta().primaryTerm(primaryTerm);
        }
        return builder;
    }