code: public void closeConnection(String name, String reason) {
      final URI uri = uriWithPath("./connections/" + encodePathSegment(name));
  
      MultiValueMap<String, String> headers = new LinkedMultiValueMap<String, String>();
      headers.put("X-Reason", Collections.singletonList(reason));
  
      deleteIgnoring404(uri, headers);
    }
docs: Forcefully closes individual connection with a user-provided message.
  The client will receive a <i>connection.close</i> method frame.
  
  @param name connection name
  @param reason the reason of closing