private function handleSend()
    {
        $flow = null;
        if ($this->writtenFlow !== null) {
            $flow = $this->writtenFlow;
            $this->writtenFlow = null;
        }

        if (count($this->sendingFlows) > 0) {
            $this->writtenFlow = array_shift($this->sendingFlows);
            $this->stream->write($this->writtenFlow->getPacket());
        }

        if ($flow !== null) {
            if ($flow->isFinished()) {
                $this->loop->nextTick(function () use ($flow) {
                    $this->finishFlow($flow);
                });
            } else {
                $this->receivingFlows[] = $flow;
            }
        }
    }