Java分布式集群,使用synchronized和Redis保证Job的原子性

时间:2023-11-03 23:38:14

1.使用synchronized保证并发时,同时只会有一个请求执行该代码段;

2.在执行前先设置并获取Reids标记,先设置然后获取确保是否已经执行;SetOption.SET_IF_ABSENT 可以保证Reids如果存在Key的话就不再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("{} 尝试获取锁: {}, value:{}", ip, keyLock, value);
//必须设置和过期同时执行
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("{} 成功获取锁: {}, value:{}", ip, keyLock, value);
return true;
}
logger.info("{} 无法获取锁: {}, value:{}", ip, keyLock, value);
return false;
}catch(Exception e) {
logger.error(e.getMessage(), e);
return false;
}finally {
if(null != redisConnection) {
redisConnection.close();
}
} }