public NSObject get(NSFileSystemAttribute key) {
   if (has(key)) {
     return data.get(key.value());
   }
   return null;
 }
 public NSFileSystemAttributes set(NSFileSystemAttribute key, NSObject value) {
   data.put(key.value(), value);
   return this;
 }
 /*<methods>*/
 public boolean has(NSFileSystemAttribute key) {
   return data.containsKey(key.value());
 }