$_SERVER的兼容處理類[PHP]

<?php
/**
 * description:對$_SERVER進行兼容處理
 * author:wogu
 */
class Server
{
		public function getScheme() {
				return isset($_SERVER['HTTPS']) == 'on' ? 'https' : 'http';
		}
		
		public function getRequestFile() {
				return isset($_SERVER['PHP_SELF']) ? $_SERVER['PHP_SELF'] : $_SERVER['SCRIPT_NAME'];
		}
		
		public function getQueryString() {
				if(isset($_SERVER['QUERY_STRING'])) {
						return $_SERVER['QUERY_STRING'];
				} elseif(isset($_SERVER['REQUEST_URI'])) {
						return str_replace($this->getRequestFile(), '', $_SERVER['REQUEST_URI']);
				} elseif(isset($_SERVER['PATH_INFO'])) {
						return $_SERVER['PATH_INFO'];
				}
				
				return '';
		}
		
		public function getDomain() {
				return $_SERVER['HTTP_HOST'];
		}
}

$server = new Server();
echo $server->getScheme() . '://' . $server->getDomain() . $server->getRequestFile() . (($qs = $server->getQueryString()) ? '?' . $qs : '');