Facebook SDK 3.18 - replacement for the deprecated facebook constructor

Question

I am now using the new Facebook SDK 3.18, i am manually checking if the native app is present or not, if app not present the open the Webview to login.

But the new sdk says that the its deprecated, but they have included the classes in the new SDK as well.

deprecated lines :

facebook = new Facebook("app_id");
facebook.setAccessToken(access_token);

if (!facebook.isSessionValid()) {
            facebook.authorize(activity, PERMISSIONS,
                    Facebook.FORCE_DIALOG_AUTH, new DialogListener() {

facebook.getAccessToken()
facebook.getAccessExpires()

How can replace the above deprecated methods with the new one from the new SDK ?

I have tried and looked into but was not able to find any solution.