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));
}
GetExpressCheckoutDetailsResponseDetailsType responseDetail = responseHeader.getGetExpressCheckoutDetailsResponseDetails();
PayerInfoType payer = responseDetail.getPayerInfo();