面试题：在分布式系统，你能想出来几种生成唯一ID的方案？(12)_系统唯一ID是我们在设计一个系统的时候

if (datacenterId > maxDatacenterId || datacenterId < 0)
{
throw new ArgumentException(string.Format(\"datacenter Id can't be greater than %d or less than 0\" maxDatacenterId));

this.workerId = workerId;
this.datacenterId = datacenterId;

public long nextId()
{
lock (syncRoot)
{
long timestamp = timeGen();

if (timestamp < lastTimestamp)
{