Java分佈式集羣，使用synchronized和Redis保證Job的原子性

1.使用synchronized保證併發時，同時只會有一個請求執行該代碼段；

2.在執行前先設置並獲取Reids標記，先設置而後獲取確保是否已經執行；SetOption.SET_IF_ABSENT 能夠保證Reids若是存在Key的話就再也不Set；

 

public synchronized static boolean isWorking(final String keyLock, final String uuidValue,long seconds){
        
        if(null == keyLock || uuidValue == null) {
            return false;
        }
        RedisConnection redisConnection = null;
        try {
            JedisConnectionFactory jedisConnectionFactory = ac.getBean("jedisConnectionFactory", JedisConnectionFactory.class);
            StringRedisTemplate redisTemplate = new StringRedisTemplate(jedisConnectionFactory);
            String value = System.currentTimeMillis() + "::" + uuidValue;
            logger.info("{} 嘗試獲取鎖: {}, value:{}", ip, keyLock, value);
            //必須設置和過時同時執行
            redisConnection = redisTemplate.getConnectionFactory().getConnection();
            redisConnection.set(keyLock.getBytes(),
                    value.getBytes(), Expiration.seconds(seconds), SetOption.SET_IF_ABSENT);
            
            if(value.equals(redisTemplate.opsForValue().get(keyLock))){
                logger.info("{} 成功獲取鎖: {}, value:{}", ip, keyLock, value);
                return true;
            }
            logger.info("{} 沒法獲取鎖: {}, value:{}", ip, keyLock, value);
            return false;
        }catch(Exception e) {
            logger.error(e.getMessage(), e);
            return false;
        }finally {
            if(null != redisConnection) {
                redisConnection.close();
            }
        }
        
    }