void internalNotifyRegistrant(Object obj, Throwable throwable) {
   Handler handler = getHandler();
   if (handler == null) {
     clear();
   } else {
     Message message = Message.obtain();
     message.what = what;
     message.obj = new AsyncResult(userObj, obj, throwable);
     handler.sendMessage(message);
   }
 }
 public Message messageForRegistrant() {
   Handler handler = getHandler();
   Message message;
   if (handler == null) {
     clear();
     message = null;
   } else {
     message = handler.obtainMessage();
     message.what = what;
     message.obj = userObj;
   }
   return message;
 }