public void callBack(HttpServletRequest request, ShoppingCart shoppingCart, ContentBean contentBean) throws PaymentException, Exception {
CallerServices caller = new CallerServices();
caller.setAPIProfile(createProfile());
GetExpressCheckoutDetailsRequestType checkoutRequest = new GetExpressCheckoutDetailsRequestType();
checkoutRequest.setToken(token);
GetExpressCheckoutDetailsResponseType responseHeader = (GetExpressCheckoutDetailsResponseType) caller.call("GetExpressCheckoutDetails", checkoutRequest);
if (!responseHeader.getAck().equals(AckCodeType.Success)) {
throw new PaymentException(formatErrorMessage(responseHeader));
}