redis缓存工具Jedis进行跨jvm加锁（分布式应用）–不幸暂弃用–能够做第三方锁使用…

public boolean lock(String key, long timeout) {
		boolean lockSuccess = false;
		ShardedJedis shardedJedis = pool.getResource();
		try{
			long start = System.currentTimeMillis();
			String lockKey = "lock_"+key;
			do{
				long result = shardedJedis.setnx(lockKey, String.valueOf(System.currentTimeMillis()+LOCKKEY_EXPIRE_TIME*1000+1));
				if(result == 1){
					lockSuccess = true;
					break;
				}else{
					String lockTimeStr = shardedJedis.get(lockKey);
					if(StringUtils.isNumeric(lockTimeStr)){//假设key存在。锁存在
						long lockTime = Long.valueOf(lockTimeStr);
						if(lockTime < System.currentTimeMillis()){//锁已过期
							String originStr = shardedJedis.getSet(lockKey, String.valueOf(System.currentTimeMillis()+LOCKKEY_EXPIRE_TIME*1000+1));
							if(StringUtils.isNoneBlank(originStr)&&originStr.equals(lockTimeStr)){//表明锁由该线程获得
								lockSuccess = true;
								break;
							}
						}
					}
				}
				//假设不等待，则直接返回
				if(timeout == 0){
					break;
				}
				//等待300ms继续加锁
				Thread.sleep(300);
			}while((System.currentTimeMillis()-start) < timeout);

		}catch(Exception e){
			e.printStackTrace();
		}finally{
			...
		}
		return lockSuccess;
	}

	public void unLock(String key) {
		ShardedJedis shardedJedis = pool.getResource();
		try{
			String lockKey = "lock_"+key;
			shardedJedis.del(lockKey);
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			...
		}
	}