/**
  * @see	\herosphp\session\interfaces\ISession::open().
  */
 public static function open($savePath, $sessionName)
 {
     if (!self::$sessionSavePath) {
         self::$sessionSavePath = $savePath;
         //创建session目录
         if (!file_exists(self::$sessionSavePath)) {
             FileUtils::makeFileDirs(self::$sessionSavePath);
         }
     }
     //do nothing here
     return TRUE;
 }
 /**
  * @see    \herosphp\session\interfaces\ISession::start().
  * @param null $config
  * @return mixed|void
  */
 public static function start($config = null)
 {
     //初始化配置信息
     self::$config = $config;
     self::$sessionSavePath = $config["session_save_path"];
     if (!file_exists(self::$sessionSavePath)) {
         FileUtils::makeFileDirs(self::$sessionSavePath);
     }
     if (!is_writable(self::$sessionSavePath)) {
         E("session 目录" . self::$sessionSavePath . "不可写,请更改权限。");
     }
     //初始化用户ip
     self::$userIp = $_SERVER['REMOTE_ADDR'];
     session_set_save_handler(array(__CLASS__, 'open'), array(__CLASS__, 'close'), array(__CLASS__, 'read'), array(__CLASS__, 'write'), array(__CLASS__, 'destroy'), array(__CLASS__, 'gc'));
     @session_start();
 }