protected function findRedirectLinkInHeader(&$http_header)
  {
    PHPCrawlerBenchmark::start("checking_for_redirect_link");
    
    // Get redirect-URL or link from header
    $redirect_link = PHPCrawlerUtils::getRedirectURLFromHeader($http_header);
    
    // Add redirect-URL to linkcache
    if ($redirect_link != null)
    {
      // Rebuild URL
      $url_rebuild = PHPCrawlerUtils::buildURLFromLink($redirect_link, $this->baseUrlParts);
      
      // Add URL to cache
      $UrlDescriptor = new PHPCrawlerURLDescriptor($url_rebuild, $redirect_link, "", "", $this->SourceUrl->url_rebuild);
      $UrlDescriptor->is_redirect_url = true;
      $this->LinkCache->addURL($UrlDescriptor);
    }
    
     PHPCrawlerBenchmark::stop("checking_for_redirect_link");
  }