code: protected WriteFuture writeData(final NextFilter nextFilter,
              final IoBuffer data) {
          // write net data
          ProxyHandshakeIoBuffer writeBuffer = new ProxyHandshakeIoBuffer(data);
  
          LOGGER.debug("   session write: {}", writeBuffer);
  
          WriteFuture writeFuture = new DefaultWriteFuture(getSession());
          getProxyFilter().writeData(nextFilter, getSession(),
                  new DefaultWriteRequest(writeBuffer, writeFuture), true);
  
          return writeFuture;
      }
docs: Writes data to the proxy server.
  
  @param nextFilter the next filter
  @param data Data buffer to be written.