/**
  * checks whether the Resource should run, i.e. it is required by at least one of the currently
  * registered features
  *
  * @return true if the Resource is required, false otherwise
  */
 public boolean isRequired() {
   if (req == null) {
     return true;
   }
   Iterator<String> it = req.iterator();
   while (it.hasNext()) {
     if (ResourceManager.reqRegistered(it.next())) {
       return true;
     }
   }
   return false;
 }