uniqueidgenerator.php

<?php

class SomeUniqueId {

    protected $strId = '';

    public function __construct($ip, $timestamp = null)
    {
        $ids = array(
            $this->generateLocationId(),
            $this->generateHostId($ip),
            $this->generateEpochId($timestamp),
            $this->generateHexId(),
        );
        $this->strId = implode('-', $ids);
    }

    protected function generateLocationId()
    {
        // Not sure
        return 'ECL00002';
    }

    protected function generateHostId($ip)
    {
        $ips = explode('.', $ip);
        $ips = array_map('intval', $ips);

        $i = (($ips[0] ^ $ips[1] ^ $ips[2]) << 8) | $ips[3];
        return sprintf('%04x', $i);
    }

    protected function generateEpochId($timestamp = null)
    {
        if ($timestamp === null) {
            $timestamp = time();
        }

        // Make sure they are integers
        $timestamp = (int) $timestamp;

        // Java equivalent handles thread safe stuff, but since PHP does not
        // generally support threaded environment, no need for thread safety stuff
        return dechex($timestamp);
    }

    protected function generateHexId()
    {
        // Not sure
        $r = rand(0, 256);
        return sprintf('%04x', ($r << 8));
    }

    public function __toString()
    {
        return $this->strId;
    }
}

$id1 = new SomeUniqueId('127.0.0.1', time());
$id2 = new SomeUniqueId('10.0.2.1', time());
$id3 = new SomeUniqueId('192.168.100.101', time());
$id4 = new SomeUniqueId('250.220.210.251', time());
$id5 = new SomeUniqueId('251.252.253.250', time());
echo $id1."\n";
echo $id2."\n";
echo $id3."\n";
echo $id4."\n";
echo $id5."\n";

Output:

[vagrant@localhost path2dx]$ php testuniqid.php
ECL00002-7f01-54903955-1300
ECL00002-0801-54903955-d600
ECL00002-0c65-54903955-f200
ECL00002-f4fb-54903955-b800
ECL00002-fafa-54903955-a000
[vagrant@localhost path2dx]$