code: private void remove(PollController conn)
    {
      if (conn == null) {
        return;
      }
  
      JniSocketImpl socket = (JniSocketImpl) conn.getSocket();
      int nativeFd = socket.getNativeFd();
  
      if (_lifecycle.isDestroyed()) {
        return;
      }
  
      _activeCount.incrementAndGet();
  
      if (nativeFd > 0) {
        try {
          removeNative(_fd, nativeFd);
        } catch (Throwable e) {
          log.log(Level.WARNING, e.toString(), e);
          _lifecycle.toError();
        }
      }
      
      conn.toKeepaliveClose();
  
      if (_activeCount.decrementAndGet() == 0 && _lifecycle.isDestroyed()) {
        destroy();
      }
    }
docs: Removes the connection from the selection.