how to login user by facebook in smartfoxserver?

i want my user to login by facebook login ,i am using this code in client side

sfsClient.login("myext", param1, ""); and in extension response i want

if (event.params.dataObj.success) 
{ 
sfsClient.myUserId = event.params.dataObj.userId; 
currentUser.userId = event.params.dataObj.userId;; 
s开发者_如何学编程fsClient.myUserName = event.params.dataObj.userName; 
currentUser.userName = event.params.dataObj.userName; 
dispatchEvent(new myEvent(myEvent.onLogMessage, "Getting Room List")); 
sfsClient.getRoomList();

can anybody explain how should be my extensionside code,ADVANCE THANK YOU

---

i think you should use the facebook Api for java , here's a usefull link : Java Facebook Api