在C#中,實現(xiàn)Snowflake分布式ID生成的方法如下:
SnowflakeIdWorker
的類,并定義一些必要的常量和變量:public class SnowflakeIdWorker
{
private const long Twepoch = 1288834974657L;
private const int WorkerIdBits = 5;
private const int DatacenterIdBits = 5;
private const int SequenceBits = 12;
private const long MaxWorkerId = -1L ^ (-1L<< WorkerIdBits);
private const long MaxDatacenterId = -1L ^ (-1L<< DatacenterIdBits);
private const int WorkerIdShift = SequenceBits;
private const int DatacenterIdShift = SequenceBits + WorkerIdBits;
private const int TimestampLeftShift = SequenceBits + WorkerIdBits + DatacenterIdBits;
private const long SequenceMask = -1L ^ (-1L << SequenceBits);
private long _sequence;
private long _lastTimestamp;
private readonly long _workerId;
private readonly long _datacenterId;
public SnowflakeIdWorker(long workerId, long datacenterId)
{
if (workerId > MaxWorkerId || workerId < 0)
{
throw new ArgumentException($"Worker Id must be between 0 and {MaxWorkerId}");
}
if (datacenterId > MaxDatacenterId || datacenterId < 0)
{
throw new ArgumentException($"Datacenter Id must be between 0 and {MaxDatacenterId}");
}
_workerId = workerId;
_datacenterId = datacenterId;
_sequence = 0L;
_lastTimestamp = -1L;
}
}
SnowflakeIdWorker
類中,添加一個名為NextId
的方法,用于生成分布式ID:public long NextId()
{
lock (this)
{
var timestamp = GetCurrentTimestamp();
if (timestamp > _lastTimestamp)
{
_sequence = 0;
_lastTimestamp = timestamp;
}
else
{
_sequence = (_sequence + 1) & SequenceMask;
if (_sequence == 0)
{
timestamp = WaitNextMillis(_lastTimestamp);
_lastTimestamp = timestamp;
}
}
return ((timestamp - Twepoch)<< TimestampLeftShift) |
(_datacenterId<< DatacenterIdShift) |
(_workerId<< WorkerIdShift) |
_sequence;
}
}
GetCurrentTimestamp
和WaitNextMillis
,分別用于獲取當(dāng)前時間戳和等待下一毫秒:private long GetCurrentTimestamp()
{
return (long)(DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalMilliseconds;
}
private long WaitNextMillis(long lastTimestamp)
{
var timestamp = GetCurrentTimestamp();
while (timestamp <= lastTimestamp)
{
timestamp = GetCurrentTimestamp();
}
return timestamp;
}
SnowflakeIdWorker
類生成分布式ID:var idWorker = new SnowflakeIdWorker(1, 1);
var distributedId = idWorker.NextId();
Console.WriteLine("Distributed ID: " + distributedId);
這樣,你就可以使用Snowflake算法在C#中生成分布式ID了。注意,這里的workerId
和datacenterId
是用于區(qū)分不同的工作節(jié)點(diǎn)和數(shù)據(jù)中心,你需要根據(jù)實際情況進(jìn)行設(shè)置。