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Redis?????????????

??????????????????????????????????Redis????????????????????????????Redis??????????????????

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?????????Redis????????????AOP?????????????????????????????

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@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface RedisLockAnnotation {
    int lockField() default 0;
    int tryCount() default 3;
    RedisLockTypeEnum typeEnum();
    long lockTime() default 30;
}

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@Pointcut("cn.sevenyuan.demo.aop.lock.RedisLockAnnotation")
public void redisLockPC() {}
@Around("cn.sevenyuan.demo.aop.lock.RedisLockAnnotation")
public Object around(ProceedingJoinPoint pjp) throws Throwable {
    Method method = pjp.resolveMethod();
    RedisLockAnnotation annotation = method.getAnnotation(RedisLockAnnotation.class);
    RedisLockTypeEnum typeEnum = annotation.typeEnum();
    Object[] params = pjp.getArgs();
    String ukString = params[annotation.lockField()].toString();
    String businessKey = typeEnum.getUniqueKey(ukString);
    String uniqueValue = UUID.randomUUID().toString();
    try {
        boolean isLock = redisTemplate.opsForValue().setIfAbsent(businessKey, uniqueValue);
        if (!isLock) {
            throw new Exception("?????");
        }
        redisTemplate.expire(businessKey, annotation.lockTime(), TimeUnit.SECONDS);
        holderList.add(new RedisLockDefinitionHolder(businessKey, annotation.lockTime(), 
            System.currentTimeMillis(), Thread.currentThread(), annotation.tryCount()));
        return pjp.proceed();
    } catch (InterruptedException e) {
        log.error("?????");
        throw new Exception("?????");
    } catch (Exception e) {
        log.error("??????");
        throw e;
    } finally {
        redisTemplate.delete(businessKey);
        log.info("??????Key?" + businessKey);
    }
    return null;
}

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@Scheduled(fixedDelay = 2, initialDelay = 0)
public void scheduleTask() {
    Iterator
   
     iterator = holderList.iterator();
    while (iterator.hasNext()) {
        RedisLockDefinitionHolder holder = iterator.next();
        if (holder == null) {
            iterator.remove();
            continue;
        }
        // ???????
        if (redisTemplate.opsForValue().get(holder.getBusinessKey()) == null) {
            iterator.remove();
            continue;
        }
        // ????????
        long currentTime = System.currentTimeMillis();
        boolean shouldExtend = (holder.getLastModifyTime() + holder.getModifyPeriod()) <= currentTime;
        if (shouldExtend) {
            holder.setLastModifyTime(currentTime);
            redisTemplate.expire(holder.getBusinessKey(), holder.getLockTime(), TimeUnit.SECONDS);
            holder.setCurrentCount(holder.getCurrentCount() + 1);
            log.info("???????Key?" + holder.getBusinessKey() + ", try count?" + holder.getCurrentCount());
        }
    }
}
   

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