redis实现的分布式锁

• 使用redis实现的分布式锁主要有两点要注意：1.对redis的操作保持原子。2.保持谁加的锁谁释放。原理比较简单，不用细说了

    private static final int LOCK_SECOND = 60;
    private static final String UNLOCK_SCRIPT = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
    private static final String LOCK_SUCC = "OK";
    private static final Long UNLOCK_SUCC = 1L;

    public String lock(String key) {
        if (StringUtils.isBlank(key)) {
            return StringUtils.EMPTY;
        }
        key = StringAssist.joinUnderline(RedisKey.DISTRIBUTED_LOCK_PRE, key);
        String uuid = UUID.randomUUID().toString();
        try (Jedis jedis = pool.getResource()) {
            String setRet = jedis.set(key, uuid, "NX", "EX", LOCK_SECOND);
            if (StringUtils.equals(setRet, LOCK_SUCC)) { // 设置成功
                return uuid;
            }
            // 设置失败
            return StringUtils.EMPTY;
        } catch (Exception e) {
            log.error("lock error, key:{}", key, e);
            return StringUtils.EMPTY;
        }
    }

    public boolean unlock(String key, String uuid) {
        if (StringUtils.isAnyBlank(key, uuid)) {
            return false;
        }
        key = StringAssist.joinUnderline(RedisKey.DISTRIBUTED_LOCK_PRE, key);
        try (Jedis jedis = pool.getResource()) {
            Object result = jedis.eval(UNLOCK_SCRIPT, Collections.singletonList(key), Collections.singletonList(uuid));
            if (UNLOCK_SUCC.equals(result)) {
                return true;
            }
            return false;
        } catch (Exception e) {
            log.error("unlock error, key:{}", key, e);
            return false;
        }
    }

• 注意，这是redis官网的写法~品质有保证