public String toNVPString(String prefix) throws UnsupportedEncodingException {
   StringBuilder sb = new StringBuilder();
   if (requestEnvelope != null) {
     String newPrefix = prefix + "requestEnvelope.";
     sb.append(requestEnvelope.toNVPString(newPrefix));
   }
   if (attributeList != null) {
     String newPrefix = prefix + "attributeList.";
     sb.append(attributeList.toNVPString(newPrefix));
   }
   return sb.toString();
 }
  /** @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    // TODO Auto-generated method stub
    HttpSession session = request.getSession();
    session.setAttribute("url", request.getRequestURI());
    session.setAttribute(
        "relatedUrl",
        "<ul><li><a href='RequestPermissions'>RequestPermissions</a></li><li><a href='GetAccessToken'>GetAccessToken</a></li><li><a href='GetPermissions'>GetPermissions</a></li><li><a href='CancelPermissions'>CancelPermissions</a></li><li><a href='GetBasicPersonalData'>GetBasicPersonalData</a></li><li><a href='GetAdvancedPersonalData'>GetAdvancedPersonalData</a></li></ul>");

    GetAdvancedPersonalDataRequest req = new GetAdvancedPersonalDataRequest();
    /*
     * (Required) RFC 3066 language in which error messages are returned; by
     * default it is en_US, which is the only language currently supported.
     */
    RequestEnvelope requestEnvelope = new RequestEnvelope("en_US");
    req.setRequestEnvelope(requestEnvelope);

    /*
     * The attributes whose value you are requesting. You specify one or
     * more of the following URIs:
     *
     * http://axschema.org/birthDate - Date of birth
     * http://axschema.org/contact/postalCode/home - Postcode
     * http://schema.openid.net/contact/street1 - Street1
     * http://schema.openid.net/contact/street2 - Street2
     * http://axschema.org/contact/city/home - City
     * http://axschema.org/contact/state/home - State
     * http://axschema.org/contact/phone/default - Phone
     */
    List<PersonalAttribute> lst = new ArrayList<PersonalAttribute>();
    String check[] = request.getParameterValues("attr");
    for (int i = 0; i < check.length; i++) {
      lst.add(PersonalAttribute.fromValue(check[i]));
    }
    PersonalAttributeList attribute = new PersonalAttributeList();
    attribute.setAttribute(lst);
    req.setAttributeList(attribute);

    SignatureCredential cred = null;
    if (request.getParameter("accessToken") != null
        && request.getParameter("accessToken").length() > 0
        && request.getParameter("tokenSecret") != null
        && request.getParameter("tokenSecret").length() > 0) {
      // The access token that identifies a set of permissions.
      // The secret associated with the access token.
      ThirdPartyAuthorization thirdPartyAuth =
          new TokenAuthorization(
              request.getParameter("accessToken"), request.getParameter("tokenSecret"));

      cred =
          new SignatureCredential(
              "jb-us-seller_api1.paypal.com",
              "WX4WTU3S8MY44S7F",
              "AFcWxV21C7fd0v3bYYYRCpSSRl31A7yDhhsPUU2XhtMoZXsWHFxu-RWy");

      cred.setApplicationId("APP-80W284485P519543T");
      cred.setThirdPartyAuthorization(thirdPartyAuth);
    }
    // ## Creating service wrapper object
    // Creating service wrapper object to make API call
    // Configuration map containing mode and other required configuration.
    // For a full list of configuration parameters refer in wiki page.
    // (https://github.com/paypal/sdk-core-java/wiki/SDK-Configuration-Parameters)
    PermissionsService service = new PermissionsService(Configuration.getAcctAndConfig());
    try {

      // ## Making API call
      // Invoke the appropriate method corresponding to API in service
      // wrapper object
      GetAdvancedPersonalDataResponse resp = null;
      if (cred != null) {
        resp = service.getAdvancedPersonalData(req, cred);
      } else {
        resp = service.getAdvancedPersonalData(req);
      }
      response.setContentType("text/html");
      if (resp != null) {
        session.setAttribute("RESPONSE_OBJECT", resp);
        session.setAttribute("lastReq", service.getLastRequest());
        session.setAttribute("lastResp", service.getLastResponse());
        if (resp.getResponseEnvelope().getAck().toString().equalsIgnoreCase("SUCCESS")) {
          Map<Object, Object> map = new LinkedHashMap<Object, Object>();
          /*
           * Acknowledgement code. It is one of the following values:
           *
           * Success - The operation completed successfully. Failure -
           * The operation failed. Warning - Warning.
           * SuccessWithWarning - The operation completed
           * successfully; however, there is a warning message.
           * FailureWithWarning - The operation failed with a warning
           * message.
           */
          map.put("Ack", resp.getResponseEnvelope().getAck());
          Iterator<PersonalData> iterator = resp.getResponse().getPersonalData().iterator();
          int index = 1;
          while (iterator.hasNext()) {
            PersonalData personalData = iterator.next();
            /*
             * The attributes whose values you are requesting. You
             * specify one or more of the following URIs:
             *
             * http://axschema.org/namePerson/first - First name
             * http://axschema.org/namePerson/last - last name
             * http://axschema.org/contact/email - Email
             * http://schema.openid.net/contact/fullname - Full name
             * http://openid.net/schema/company/name - Business name
             * http://axschema.org/contact/country/home - Country
             * https://www.paypal.com/webapps/auth/schema/payerID -
             * Payer ID
             */
            map.put("PersonalDataKey" + index, personalData.getPersonalDataKey().getValue());

            // The value associated with the key
            map.put("PersonalDataValue" + index, personalData.getPersonalDataValue());
            index++;
          }

          session.setAttribute("map", map);
          response.sendRedirect("Response.jsp");
        } else {
          session.setAttribute("Error", resp.getError());
          response.sendRedirect("Error.jsp");
        }
      }

    } catch (OAuthException e) {
      // TODO: handle exception
      e.printStackTrace();
    } catch (SSLConfigurationException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (InvalidCredentialException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (HttpErrorException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (InvalidResponseDataException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (ClientActionRequiredException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (MissingCredentialException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (InterruptedException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }