models/classes/runner/communicator/QtiCommunicationService.php
protected function hasChannel($channelName, $channelType)
    {
        $channels = $this->getOption(self::OPTION_CHANNELS);
        return isset($channels[$channelType][$channelName]);
    }
protected function hasChannel($channelName, $channelType)
    {
        $channels = $this->getOption(self::OPTION_CHANNELS);
        return isset($channels[$channelType][$channelName]);
    }
Check whether channel exists
@param string $channelName
@param integer $channelType
@return bool