redis分布式锁

public class RedisTool {
    private static final String LOCK_SUCCESS = "OK";
    private static final String SET_IF_NOT_EXIST = "NX";
    private static final String SET_WITH_EXPIRE_TIME = "PX";
    /**
     * 尝试获取分布式锁
     * @param jedis Redis客户端
     * @param lockKey 锁
     * @param requestId 请求标识
     * @param expireTime 超期时间
     * @return 是否获取成功
     */
    public static boolean tryGetDistributedLock(Jedis jedis, String lockKey, String requestId, int expireTime) {
        String result = jedis.set(lockKey, requestId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, expireTime);
        if (LOCK_SUCCESS.equals(result)) {
            return true;
        }
        return false;
    }

public class RedisTool {
    private static final Long RELEASE_SUCCESS = 1L;
    /**
     * 释放分布式锁
     * @param jedis Redis客户端
     * @param lockKey 锁
     * @param requestId 请求标识
     * @return 是否释放成功
     */
    public static boolean releaseDistributedLock(Jedis jedis, String lockKey, String requestId) {
        String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
        Object result = jedis.eval(script, Collections.singletonList(lockKey), Collections.singletonList(requestId));
        if (RELEASE_SUCCESS.equals(result)) {
            return true;
        }
        return false;
    }
}
参考：https://mp.weixin.qq.com/s/qJK61ew0kCExvXrqb7-RSg
https://xiaomi-info.github.io/2019/12/17/redis-distributed-lock/
-----------下列方法错误：如果在setnx和expire 中间服务挂掉则出现问题------------
1.使用setNx做分布式锁：setnx只能设置一次值，第二次会设置失败
```java
public Boolean setSecondTime(String key, String value, Long secondTime) {
        try {
            boolean flag= client.setNX(key, value);
            client.expire(key, secondTime, TimeUnit.SECONDS);
        } catch (Exception e) {
            log.error("jimdbservice setSecondTime", e);
        }
        return flag;
    }

try {
            if (boardJimdbService.setSecondTime(Sale_Task_key, "111", 8L)) {
                //TODO
            }
        } catch (Exception e) {
        } finally {
            boardJimdbService.del(Sale_Task_key);
}