public Seckill getSeckill(long seckillId) {
        String key = "seckill:" + seckillId;
        Seckill seckill = (Seckill) redisTemplate.opsForValue().get(key);
        if (seckill != null) {
            return seckill;
        } else {
            seckill = seckillMapper.selectById(seckillId);
            if (seckill == null) {
                throw new RuntimeException("秒杀活动不存在！");
            }
            putSeckill(seckill);
            return seckill;
        }
    }
@Test
    void getSeckillError() {
        long seckillId = 1001L;
        when(redisTemplate.opsForValue()).thenReturn(mock(ValueOperations.class));
        assertThrows(RuntimeException.class, () -> redisService.getSeckill(seckillId));
    }