@Override
 public boolean matches(Challenge c) {
   final LinkCrawler lcrawler = getCrawler();
   if (lcrawler != null && lcrawler.isRunning()) {
     final Plugin plugin = c.getPlugin();
     if (plugin instanceof PluginForDecrypt) {
       final PluginForDecrypt decrypt = (PluginForDecrypt) plugin;
       return decrypt.getCrawler() == lcrawler && decrypt.getHost().equalsIgnoreCase(getHost());
     }
   }
   return false;
 }