public function readUuid($isCollectionElement = false)
{
if ($isCollectionElement) {
$this->readShort();
}
$uuid = '';
$data = $this->read(16);
for ($i = 0; $i < 16; ++$i) {
if ($i == 4 || $i == 6 || $i == 8 || $i == 10) {
$uuid .= '-';
}
$uuid .= str_pad(dechex(ord($data[$i])), 2, '0', STR_PAD_LEFT);
}
return $uuid;
}