code: public static void fetchDeferredAppLinkData(
              Context context,
              String applicationId,
              final CompletionHandler completionHandler) {
          Validate.notNull(context, "context");
          Validate.notNull(completionHandler, "completionHandler");
  
          if (applicationId == null) {
              applicationId = Utility.getMetadataApplicationId(context);
          }
  
          Validate.notNull(applicationId, "applicationId");
  
          final Context applicationContext = context.getApplicationContext();
          final String applicationIdCopy = applicationId;
          Settings.getExecutor().execute(new Runnable() {
              @Override
              public void run() {
                  fetchDeferredAppLinkFromServer(applicationContext, applicationIdCopy, completionHandler);
              }
          });
      }
docs: Asynchronously fetches app link information that might have been stored for use
  after installation of the app
  @param context The context
  @param applicationId Facebook application Id. If null, it is taken from the manifest
  @param completionHandler CompletionHandler to be notified with the AppLinkData object or null if none is
  available.  Must not be null.