docs: @Handler
      @SuppressWarnings("PMD.DataflowAnomalyAnalysis")
      public void onClose(Close event) throws IOException, InterruptedException {
          for (Channel channel : event.channels()) {
              if (channel instanceof TcpChannelImpl
                  && channels.contains(channel)) {
                  ((TcpChannelImpl) channel).close();
              }
          }
      }