final long timestamp = propertiesFile.lastModified();
        if (timestamp <= lastModified) {
            return false;
        }

        return true;
    }

    public synchronized void load() {
        final Properties prop = new Properties();
        try (final FileInputStream fis = new FileInputStream(propertiesFile)) {
            lastModified = propertiesFile.lastModified();
            prop.load(fis);

        this.contentLength = contentLength;
    }

    @Override
    public Long getLastModified() {
        return lastModified;
    }

    @Override
    public void setLastModified(final Long lastModified) {
        this.lastModified = lastModified;
    }

    @Override
    public String toString() {

// generates CopyObjectResponse from etag and lastModified time.
func generateCopyObjectResponse(etag string, lastModified time.Time) CopyObjectResponse {
	return CopyObjectResponse{
		ETag:         "\"" + etag + "\"",
		LastModified: amztime.ISO8601Format(lastModified.UTC()),
	}
}

// generates CopyObjectPartResponse from etag and lastModified time.

            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) {

    private var servedDate: Date? = null
    private var servedDateString: String? = null

    /** The last modified date of the cached response, if known. */
    private var lastModified: Date? = null
    private var lastModifiedString: String? = null

    /**
     * The expiration date of the cached response, if known. If both this field and the max age are
     * set, the max age is preferred.

        }
        if (contentLength != null) {
            builder.field(CONTENT_LENGTH, contentLength);
        }
        if (lastModified != null) {
            builder.field(LAST_MODIFIED, lastModified);
        }
        if (accessResultData instanceof ToXContent) {
            builder.field(ACCESS_RESULT_DATA);
            ((ToXContent) accessResultData).toXContent(builder, params);

        if (parentUrl != null) {
            builder.field(PARENT_URL, parentUrl);
        }
        if (depth != null) {
            builder.field(DEPTH, depth);
        }
        if (lastModified != null) {
            builder.field(LAST_MODIFIED, lastModified);
        }
        if (createTime != null) {
            builder.field(CREATE_TIME, createTime);
        }
        builder.field(WEIGHT, weight);
        builder.endObject();

     */
    @Override
    public Long getLastModified() {
        return lastModified;
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.entity.UrlQueue#setLastModified(java.sql.Long)
     */
    @Override
    public void setLastModified(final Long lastModified) {
        this.lastModified = lastModified;
    }

    @Override
    public float getWeight() {

            final long timestamp = reloadableFile.lastModified();
            if (timestamp != time) {
                synchronized (reloadableFile) {
                    if (timestamp != lastModified) {
                        createSynonymMap(true);
                        return true;
                    }
                }
            }
        }

        if (lastModified != time) {
            return true;
        }

            if (synonymLoader.isReloadable()) {
                this.synonymLoader = synonymLoader;
                this.lastModified = synonymLoader.getLastModified();
            } else {
                this.synonymLoader = null;
                this.lastModified = System.currentTimeMillis();
            }
            synonymMap = synonymLoader.getSynonymMap();