Map<String, Integer> locks = lockHolder.get(); if (locks != null && locks.containsKey(lockKey)) { int counter = locks.get(lockKey); if (counter > 1) { // 锁是可重入的,计数器减1 locks.put(lockKey, counter - 1); } else { // 锁完全释放,从线程本地变量中移除 locks.remove(loc...
2）创建RedissonMultiLock对象，并将各节点对应的锁加入到RedissonMultiLock对象的locks集合中。3）遍历locks集合，执行集合中每个节点对应锁的tryLock()方法尝试获取锁：获取成功，则将锁加入到RedissonMultiLock对象的acquiredLocks集合中，判断RedissonMultiLock是否设置了有效期（即：自定义锁的过期时长）：是则判断是否超时...
failedLocksLimit:MultiLock中返回0,RedLock中返回locks.size() / 2 - 1。 calcLockWaitTime:MultiLock中返回remainTime,RedLock中返回Math.max(remainTime / (long)this.locks.size(), 1L)。 通过源码容易看到,Redisson中的 RedLock算法完全是基于 MultiLock实现的。Redisson 支持这种“联合锁”的概念,将多个 RLock...
当客户端需要获取锁时,会尝试顺序从N个实例中获取,在所有实例中使用相同的key与value。 官方文档:https://redis.io/docs/manual/patterns/distributed-locks 使用方式:https://github.com/wujunwei/redlock/blob/master/README.md 4.1 获取锁: 当N / 2 + 1个节点获取到锁时则成功得到锁(因为如果小于一半判断...
import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.Lock; class RedisDistributedLock implements Lock { private StringRedisTemplate stringRedisTemplate; private String lockName; // KEYS[1] 锁名字 private String uuidValue; // ARGV[1] 值 private long expireTime; // ARGV[...
locks.redis[key]=1returnTrue defunlock(client,user_id):key=key_for(user_id)ifkeyinlocks.redis:locks.redis[key]-=1iflocks.redis[key]<=0:del locks.redis[key]returnTruereturnFalse client=redis.StrictRedis()print"lock",lock(client,"codehole")print"lock",lock(client,"codehole")print"unlock...
acquiredLocks.add(lock); } else { // 如果达到了允许加锁失败节点限制,那么break,即此次Redlock加锁失败 if (locks.size() - acquiredLocks.size() == failedLocksLimit()) { break; } } } return true; } 1. 2. 3. 4. 5. 6. 7.
lockedLocks.add(lock); }else{// 如果不能保证获取至少 N/2 + 1 把锁,就结束if(locks.size() - lockedLocks.size() == failedLocksLimit()) {break; }// 获取锁失败超过了一定次数if(failedLocksLimit ==0) { unlockInner(lockedLocks);if(waitTime == -1&& leaseTime == -1) {returnfalse; ...
importorg.springframework.data.redis.core.script.RedisScript;importjava.util.ArrayList;importjava.util.List;importjava.util.concurrent.TimeUnit;importjava.util.concurrent.locks.Condition;importjava.util.concurrent.locks.Lock;@Slf4j@Data@AllArgsConstructorpublicclassJedisLockimplementsLock{privateRedisTemplate ...