微信oauth2的access_token问题

<?phprequire_once("weixin.config.php");class Webweixin{	//APPID 默认是服务号	var $APPID = APPID1;	var $APPSECRET = APPSECRET1;		//用户方信息（存储当前交互用户的操作状态，以及状态时效）	var $_client = array('wx_id'=>'', 'user_id'=>0, 'act'=>'', 'exp'=>0, 'token'=>'','userdata'=>'');	var $wxu_mod;	var $CODE = '';	    function __construct()    {		$this->APPID = APPID1;		$this->APPSECRET = APPSECRET1;				if (isset($_GET['code']))		{			$this->CODE =  $_GET['code'];			$userinfo = $this->getUserInfo();			dump($userinfo);		}    }		public function getUserInfo()	{		$accessToken = $this->getAccessToken();				$cfg['ssl'] = true;		//https://api.weixin.qq.com/sns/userinfo?access_token=ACCESS_TOKEN&openid=OPENID		$userinfo = $this->__curlOpen("https://api.weixin.qq.com/sns/userinfo?access_token=".$accessToken."&openid=".$this->_client['wx_id'].'&lang=zh_CN', $cfg);		$userinfo = json_decode($userinfo,true);		return $userinfo;	}		/**	 * 获取ACCESS TOKEN	 */	public function getAccessToken($getHTTP = false)	{		$isCurl = true;		/*		$tokenfile = ROOT_PATH . "/temp/TOKEN_WEB";		$token = file_exists($tokenfile)?file_get_contents($tokenfile):'';		if($token)		{			$token = json_decode($token,true);			if( time()-$token['access_time'] < $token['expires_in']){				$isCurl = false;			}		}*/        if($isCurl || $getHTTP)		{			//https://api.weixin.qq.com/sns/oauth2/access_token?appid=APPID&secret=SECRET&code=CODE&grant_type=authorization_code			$cfg['ssl'] = true;			$token = $this->__curlOpen("https://api.weixin.qq.com/sns/oauth2/access_token?appid=".$this->APPID."&secret=".$this->APPSECRET."&code=".$this->CODE."&grant_type=authorization_code", $cfg);			$token = json_decode($token,true);			$token['access_time'] = time();			//file_put_contents($tokenfile, json_encode($token), LOCK_EX);		}				$this->_client['wx_id'] = $token['openid'];		$client = $this->wx_user();		if($client){			$this->_client = $client;		}else{			$this->wx_user('add');		}		return $token['access_token'];	}    		public function __curlOpen($url, $cfg)	{		$ch = curl_init();		curl_setopt($ch, CURLOPT_URL, $url);		isset($cfg['post']) && curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");		if($cfg['ssl'])		{			curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);			curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);		}		curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (compatible; MSIE 5.01; Windows NT 5.0)');		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);		curl_setopt($ch, CURLOPT_AUTOREFERER, 1);		isset($cfg['post']) && curl_setopt($ch, CURLOPT_POSTFIELDS, $cfg['post']);		curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);				$result = curl_exec($ch);		if (curl_errno($ch))		{			return curl_error($ch);		}		curl_close($ch);		return $result;	}		//微信用户信息操作	public function wx_user($act='')    {		if($this->_client['wx_id'])		{			$this->wxu_mod = &m("weixinuser");			if($act=='add')			{				$this->wxu_mod->add($this->_client);			}elseif($act=='edit'){				$this->wxu_mod->edit("wx_id='".$this->_client['wx_id']."'", $this->_client);			}else{				$client = $this->wxu_mod->get("wx_id='".$this->_client['wx_id']."'");				return $client;			}		}	}	/*$scope : snsapi_base / snsapi_userinfo*/	public function makeStartUrl($url, $state = '', $scope = 'snsapi_userinfo')	{		//https://open.weixin.qq.com/connect/oauth2/authorize?appid=APPID&redirect_uri=REDIRECT_URI&response_type=code&scope=SCOPE&state=STATE#wechat_redirect		$base_url = "https://open.weixin.qq.com/connect/oauth2/authorize?appid={$this->APPID}&redirect_uri=";		$base_url .= rawurlencode($url);		$base_url .= "&response_type=code&scope={$scope}&state={$state}#wechat_redirect";				return $base_url;	}}?>