vip-augus/springboot-note

Spring Boot+Vue 书籍学习 demo

springboot-note's Issues

释放锁代码存在问题，会存在超时操作释放了本次操作的锁

finally {
        // 请求结束后，强制删掉 key，释放锁
        redisTemplate.delete(businessKey);
        log.info("release the lock, businessKey is [" + businessKey + "]");
    }

如果A线程锁操作超时了，但是还在执行，此时B线程进入了拿到锁并进行操作，此时A线程去释放锁，释放的就是B此时持有的锁。
此处应该加入判断，来释放锁的线程是否是持有锁的那个线程。
可以改成
finally {
try {
RedisLockDefinitionHolder redisLockDefinitionHolder = holderList.stream().filter(h -> businessKey.equals(h.getBusinessKey())).findFirst().orElse(null);
if (redisLockDefinitionHolder != null && redisLockDefinitionHolder.getCurrentTread().equals(currentThread)){
// 请求结束后，强制删掉 key，释放锁
redisTemplate.delete(businessKey);
log.info("release the lock, businessKey is [" + businessKey + "]");
}
}catch(Exception e){
log.error("release the lock error", e);
}
}

redis加错未采用原子操作

boolean isSuccess = redisTemplate.opsForValue().setIfAbsent(businessKey, uniqueValue);
        if (!isSuccess) {
            throw new Exception("You can't do it，because another has get the lock =-=");
        }
        redisTemplate.expire(businessKey, annotation.lockTime(), TimeUnit.SECONDS);

这块redis操作，不是原子的，如果在设置过期时间前，突然宕机了，则加锁后的key将长时间存在，
应该用
Boolean setIfAbsent(K key, V value, long timeout, TimeUnit unit);