/**
?*?線程池，每個(gè)?JVM?使用一個(gè)線程去維護(hù)?keyAliveTime，定時(shí)執(zhí)行?runnable
?*/
private?static?final?ScheduledExecutorService?SCHEDULER?=?
new?ScheduledThreadPoolExecutor(1,?
new?BasicThreadFactory.Builder().namingPattern("redisLock-schedule-pool").daemon(true).build());
static?{
????SCHEDULER.scheduleAtFixedRate(()?->?{
????????//?do?something?to?extend?time
????},?0,??2,?TimeUnit.SECONDS);
}

public?enum?RedisLockTypeEnum?{
????/**
?????*?自定義?key?前綴
?????*/
????ONE("Business1",?"Test1"),
????
????TWO("Business2",?"Test2");
????private?String?code;
????private?String?desc;
????RedisLockTypeEnum(String?code,?String?desc)?{
????????this.code?=?code;
????????this.desc?=?desc;
????}
????public?String?getCode()?{
????????return?code;
????}
????public?String?getDesc()?{
????????return?desc;
????}
????public?String?getUniqueKey(String?key)?{
????????return?String.format("%s:%s",?this.getCode(),?key);
????}
}

public?class?RedisLockDefinitionHolder?{
????/**
?????*?業(yè)務(wù)唯一?key
?????*/
????private?String?businessKey;
????/**
?????*?加鎖時(shí)間?(秒?s)
?????*/
????private?Long?lockTime;
????/**
?????*?上次更新時(shí)間（ms）
?????*/
????private?Long?lastModifyTime;
????/**
?????*?保存當(dāng)前線程
?????*/
????private?Thread?currentTread;
????/**
?????*?總共嘗試次數(shù)
?????*/
????private?int?tryCount;
????/**
?????*?當(dāng)前嘗試次數(shù)
?????*/
????private?int?currentCount;
????/**
?????*?更新的時(shí)間周期（毫秒）,公式?=?加鎖時(shí)間（轉(zhuǎn)成毫秒）?/?3
?????*/
????private?Long?modifyPeriod;
????public?RedisLockDefinitionHolder(String?businessKey,?Long?lockTime,?Long?lastModifyTime,?Thread?currentTread,?int?tryCount)?{
????????this.businessKey?=?businessKey;
????????this.lockTime?=?lockTime;
????????this.lastModifyTime?=?lastModifyTime;
????????this.currentTread?=?currentTread;
????????this.tryCount?=?tryCount;
????????this.modifyPeriod?=?lockTime?*?1000?/?3;
????}
}

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD,?ElementType.TYPE})
public?@interface?RedisLockAnnotation?{
????/**
?????*?特定參數(shù)識(shí)別，默認(rèn)取第?0?個(gè)下標(biāo)
?????*/
????int?lockFiled()?default?0;
????/**
?????*?超時(shí)重試次數(shù)
?????*/
????int?tryCount()?default?3;
????/**
?????*?自定義加鎖類型
?????*/
????RedisLockTypeEnum?typeEnum();
????/**
?????*?釋放時(shí)間，秒?s?單位
?????*/
????long?lockTime()?default?30;
}

/**
?*?@annotation?中的路徑表示攔截特定注解
?*/
@Pointcut("@annotation(cn.sevenyuan.demo.aop.lock.RedisLockAnnotation)")
public?void?redisLockPC()?{
}

@Around(value?=?"redisLockPC()")
public?Object?around(ProceedingJoinPoint?pjp)?throws?Throwable?{
????//?解析參數(shù)
????Method?method?=?resolveMethod(pjp);
????RedisLockAnnotation?annotation?=?method.getAnnotation(RedisLockAnnotation.class);
????RedisLockTypeEnum?typeEnum?=?annotation.typeEnum();
????Object[]?params?=?pjp.getArgs();
????String?ukString?=?params[annotation.lockFiled()].toString();
????//?省略很多參數(shù)校驗(yàn)和判空
????String?businessKey?=?typeEnum.getUniqueKey(ukString);
????String?uniqueValue?=?UUID.randomUUID().toString();
????//?加鎖
????Object?result?=?null;
????try?{
????????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);
????????Thread?currentThread?=?Thread.currentThread();
????????//?將本次?Task?信息加入「延時(shí)」隊(duì)列中
????????holderList.add(new?RedisLockDefinitionHolder(businessKey,?annotation.lockTime(),?System.currentTimeMillis(),
????????????????currentThread,?annotation.tryCount()));
????????//?執(zhí)行業(yè)務(wù)操作
????????result?=?pjp.proceed();
????????//?線程被中斷，拋出異常，中斷此次請(qǐng)求
????????if?(currentThread.isInterrupted())?{
????????????throw?new?InterruptedException("You?had?been?interrupted?=-=");
????????}
????}?catch?(InterruptedException?e?)?{
????????log.error("Interrupt?exception,?rollback?transaction",?e);
????????throw?new?Exception("Interrupt?exception,?please?send?request?again");
????}?catch?(Exception?e)?{
????????log.error("has?some?error,?please?check?again",?e);
????}?finally?{
????????//?請(qǐng)求結(jié)束后，強(qiáng)制刪掉?key，釋放鎖
????????redisTemplate.delete(businessKey);
????????log.info("release?the?lock,?businessKey?is?["?+?businessKey?+?"]");
????}
????return?result;
}

//?掃描的任務(wù)隊(duì)列
private?static?ConcurrentLinkedQueue<RedisLockDefinitionHolder>?holderList?=?new?ConcurrentLinkedQueue();
/**
?*?線程池，維護(hù)keyAliveTime
?*/
private?static?final?ScheduledExecutorService?SCHEDULER?=?new?ScheduledThreadPoolExecutor(1,
????????new?BasicThreadFactory.Builder().namingPattern("redisLock-schedule-pool").daemon(true).build());
{
????//?兩秒執(zhí)行一次「續(xù)時(shí)」操作
????SCHEDULER.scheduleAtFixedRate(()?->?{
????????//?這里記得加?try-catch，否者報(bào)錯(cuò)后定時(shí)任務(wù)將不會(huì)再執(zhí)行=-=
????????Iterator<RedisLockDefinitionHolder>?iterator?=?holderList.iterator();
????????while?(iterator.hasNext())?{
????????????RedisLockDefinitionHolder?holder?=?iterator.next();
????????????//?判空
????????????if?(holder?==?null)?{
????????????????iterator.remove();
????????????????continue;
????????????}
????????????//?判斷?key?是否還有效，無(wú)效的話進(jìn)行移除
????????????if?(redisTemplate.opsForValue().get(holder.getBusinessKey())?==?null)?{
????????????????iterator.remove();
????????????????continue;
????????????}
????????????//?超時(shí)重試次數(shù)，超過(guò)時(shí)給線程設(shè)定中斷
????????????if?(holder.getCurrentCount()?>?holder.getTryCount())?{
????????????????holder.getCurrentTread().interrupt();
????????????????iterator.remove();
????????????????continue;
????????????}
????????????//?判斷是否進(jìn)入最后三分之一時(shí)間
????????????long?curTime?=?System.currentTimeMillis();
????????????boolean?shouldExtend?=?(holder.getLastModifyTime()?+?holder.getModifyPeriod())?<=?curTime;
????????????if?(shouldExtend)?{
????????????????holder.setLastModifyTime(curTime);
????????????????redisTemplate.expire(holder.getBusinessKey(),?holder.getLockTime(),?TimeUnit.SECONDS);
????????????????log.info("businessKey?:?["?+?holder.getBusinessKey()?+?"],?try?count?:?"?+?holder.getCurrentCount());
????????????????holder.setCurrentCount(holder.getCurrentCount()?+?1);
????????????}
????????}
????},?0,?2,?TimeUnit.SECONDS);
}

@GetMapping("/testRedisLock")
@RedisLockAnnotation(typeEnum?=?RedisLockTypeEnum.ONE,?lockTime?=?3)
public?Book?testRedisLock(@RequestParam("userId")?Long?userId)?{
????try?{
????????log.info("睡眠執(zhí)行前");
????????Thread.sleep(10000);
????????log.info("睡眠執(zhí)行后");
????}?catch?(Exception?e)?{
????????//?log?error
????????log.info("has?some?error",?e);
????}
????return?null;
}