public final function __toString()
{
$headerPacket = pack("CCnnCC", $this->version, $this->type, $this->requestId, $this->contentLength, $this->paddingLength, $this->reserved);
$payloadPacket = $this->packPayload();
$paddingPacket = pack("a{$this->paddingLength}", $this->paddingData);
return $headerPacket . $payloadPacket . $paddingPacket;
}