雪花算法 PHP 创建唯一id

<?php
namespace service;
class SnowFlake
{
   
    const EPOCH = 1479533469598;
    const max12bit = 4095;
    const max41bit = 1099511627775; 
    static $machineId = null; 
    public function __construct($mId = 0){
   
        self::$machineId = $mId;
    }