public void setExpireTimeSeconds(long expireTimeSeconds) {
        customHeaders.put("Cache-Control", "private, max-age=" + expireTimeSeconds);
        customHeaders.put("Expires", new Date(System.currentTimeMillis() + (expireTimeSeconds * 1000)).toString());
    }
Configures location for static resources

@param folder the location
src/main/java/spark/staticfiles/StaticFilesConfiguration.java