Redisson 可重入锁原理

获取锁：

Redisson 获取锁源代码：

return evalWriteAsync(getName(), LongCodec.INSTANCE, command,
    "if (redis.call('exists', KEYS[1]) == 0) then " +
            "redis.call('hincrby', KEYS[1], ARGV[2], 1); " +
            "redis.call('pexpire', KEYS[1], ARGV[1]); " +
            "return nil; " +
            "end; " +
            "if (redis.call('hexists', KEYS[1], ARGV[2]) == 1) then " +
            "redis.call('hincrby', KEYS[1], ARGV[2], 1); " +
            "redis.call('pexpire', KEYS[1], ARGV[1]); " +
            "return nil; " +
            "end; " +
            "return redis.call('pttl', KEYS[1]);",
    Collections.singletonList(getName()), internalLockLeaseTime, getLockName(threadId));

释放锁：

Redisson 释放锁源代码：

return evalWriteAsync(getName(), LongCodec.INSTANCE, RedisCommands.EVAL_BOOLEAN,
    "if (redis.call('hexists', KEYS[1], ARGV[3]) == 0) then " +
            "return nil;" +
            "end; " +
            "local counter = redis.call('hincrby', KEYS[1], ARGV[3], -1); " +
            "if (counter > 0) then " +
            "redis.call('pexpire', KEYS[1], ARGV[2]); " +
            "return 0; " +
            "else " +
            "redis.call('del', KEYS[1]); " +
            "redis.call('publish', KEYS[2], ARGV[1]); " +
            "return 1; " +
            "end; " +
            "return nil;",
    Arrays.asList(getName(), getChannelName()), LockPubSub.UNLOCK_MESSAGE, internalLockLeaseTime, getLockName(threadId));