public function setRetentionTimeWindow($retentionTimeStart, $retentionTimeEnd)
    {
        if (! (is_int($retentionTimeStart) || is_float($retentionTimeStart))) {
            throw new \InvalidArgumentException(
                'Argument 1 must be of type int or float. Value is of type ' . gettype($retentionTimeStart));
        }
        
        if (! (is_int($retentionTimeEnd) || is_float($retentionTimeEnd))) {
            throw new \InvalidArgumentException(
                'Argument 2 must be of type int or float. Value is of type ' . gettype($retentionTimeEnd));
        }
        
        $this->retentionTimeWindow = array();
        $this->retentionTimeWindow[static::RETENTION_TIME_START] = $retentionTimeStart;
        $this->retentionTimeWindow[static::RETENTION_TIME_END] = $retentionTimeEnd;
    }