/**
  * Get the extension with the given id.
  *
  * @param id the requested id.
  * @return the format data manager descriptor with the requested id if it exists.
  */
 public static FormatDataManagerDescriptor getRegisteredExtension(String id) {
   for (FormatDataManagerDescriptor desc : EXTENSIONS.keySet()) {
     if (!StringUtil.isEmpty(desc.getId()) && desc.getId().equals(id)) {
       return desc;
     }
   }
   return null;
 }