docs: public void handleError(SelectableChannel channel) {
      SocketAddress channelAddress = ((SocketChannel) channel).socket().getRemoteSocketAddress();
      LOG.info("Handling error from channel: " + channelAddress);
      SocketChannelHelper helper = activeConnections.get(channel);
      if (helper == null) {
        LOG.severe("Inactive channel had error?");
        return;
      }
      helper.clear();
      LOG.info("Removing all interest on channel: " + channelAddress);
      nioLooper.removeAllInterest(channel);
      try {
        channel.close();
      } catch (IOException e) {
        LOG.severe("Error closing connection in handleError");
      }
      activeConnections.remove(channel);
      onClose((SocketChannel) channel);
    }