FACEBOOK错误丢失类如果类包含

我错在哪里?我确实从facebook开发中心复制代码，但我不知道错误在哪里....请帮帮我;)可惜它不是经典的php…:/

<?php
require_once ('fb/facebook-php-sdk/src/Facebook/GraphObject.php');
require_once ('fb/facebook-php-sdk/src/Facebook/GraphUser.php');
require_once ('fb/facebook-php-sdk/src/Facebook/FacebookSession.php')  ;
require_once ('fb/facebook-php-sdk/src/Facebook/FacebookRequest.php');
require_once ('fb/facebook-php-sdk/src/Facebook/FacebookRequestException.php');
require_once ('fb/facebook-php-sdk/src/Facebook/FacebookSDKException.php');
use Facebook'FacebookRequest;
use Facebook'GraphUser;
use Facebook'FacebookRequestException;
use Facebook'FacebookSession;
use Facebook'GraphObject;
use Facebook'FacebookSDKException;

FacebookSession::setDefaultApplication('531817970165190', 'd589d0ae5b2a46ca1240670da41204ed');
// If you already have a valid access token:
 $sessi FacebookSession('access-token');
// If you're making app-level requests:
 $sessi
// To validate the session:
try {
  $session->validate();
} catch (FacebookRequestException $ex) {
  // Session not valid, Graph API returned an exception with the reason.
  echo $ex->getMessage();
} catch ('Exception $ex) {
  // Graph API returned info, but it may mismatch the current app or have expired.
  echo $ex->getMessage();}  

if($session) {
  try {
    $request = new FacebookRequest($session, 'GET', '/me');
 $resp>execute();
$graphObject = $response->getGraphObject();
    echo "Ahoj " . $request->getName();
  } catch(FacebookRequestException $e) {
    echo "Exception occured, code: " . $e->getCode();
    echo " with message: " . $e->getMessage();
  }  
}
?>

Fatal error: Class 'Facebook'FacebookSDKException' not found in /home/users/acerr/docasne.cekuj.net/web/fb/facebook-php-sdk/src/Facebook/FacebookRequestException.php on line 33