Page::getInstance

static function getInstance()
{
	if (!isset(static::$instance))
	{
		$cacheProvider = static::getCacheProvider();
		$privateKey = $cacheProvider !== null ? $cacheProvider->getCachePrivateKey() : null;

		static::$instance = new static(
			Helper::getRequestUri(),
			Helper::getHttpHost(),
			Helper::getRealPrivateKey($privateKey)
		);

		if ($cacheProvider !== null)
		{
			static::$instance->setCacheProvider($cacheProvider);
		}
	}

	return static::$instance;
}