public String getUriToAttachment(String commentId, ICFile attachment, User user) {
    URIUtil uri = new URIUtil(IWMainApplication.getDefaultIWMainApplication().getMediaServletURI());

    uri.setParameter(
        MediaWritable.PRM_WRITABLE_CLASS,
        IWMainApplication.getEncryptedClassName(CommentAttachmentDownloader.class));
    uri.setParameter(ArticleCommentAttachmentStatisticsViewer.COMMENT_ID_PARAMETER, commentId);
    uri.setParameter(
        ArticleCommentAttachmentStatisticsViewer.COMMENT_ATTACHMENT_ID_PARAMETER,
        attachment.getPrimaryKey().toString());

    if (user != null) {
      uri.setParameter(LoginBusinessBean.PARAM_LOGIN_BY_UNIQUE_ID, user.getUniqueId());
      uri.setParameter(LoginBusinessBean.LoginStateParameter, LoginBusinessBean.LOGIN_EVENT_LOGIN);
    }

    return uri.getUri();
  }
  @SuppressWarnings("unchecked")
  protected void processRequest(HttpServletRequest req, HttpServletResponse resp, boolean isPost)
      throws ServletException, IOException {
    ServerManager manager = getServerManager();
    IWMainApplication iwma = IWMainApplication.getIWMainApplication(req);

    // extract the parameters from the request
    ParameterList requestParameters = new ParameterList(req.getParameterMap());

    OpenIDServerBean serverBean = ELUtil.getInstance().getBean("openIDServerBean");
    ParameterList sessionStoredParameterList = serverBean.getParameterList();
    if (sessionStoredParameterList != null) {
      if (!requestParameters.hasParameter(OpenIDConstants.PARAMETER_OPENID_MODE)) {
        sessionStoredParameterList.addParams(requestParameters);
        requestParameters = sessionStoredParameterList;
      }
    }

    String mode =
        requestParameters.hasParameter(OpenIDConstants.PARAMETER_OPENID_MODE)
            ? requestParameters.getParameterValue(OpenIDConstants.PARAMETER_OPENID_MODE)
            : null;
    String realm =
        requestParameters.hasParameter(OpenIDConstants.PARAMETER_REALM)
            ? requestParameters.getParameterValue(OpenIDConstants.PARAMETER_REALM)
            : null;
    if (realm != null) {
      serverBean.setReturnUrl(realm);
      realm = getRealmName(realm);
      serverBean.setRealm(realm);
    }

    Message response;
    String responseText = null;

    try {
      if (OpenIDConstants.PARAMETER_ASSOCIATE.equals(mode)) {
        // --- process an association request ---
        response = manager.associationResponse(requestParameters);
        responseText = response.keyValueFormEncoding();
      } else if (OpenIDConstants.PARAMETER_CHECKID_SETUP.equals(mode)
          || OpenIDConstants.PARAMETER_CHECKID_IMMEDIATE.equals(mode)) {
        IWContext iwc = new IWContext(req, resp, getServletContext());

        boolean goToLogin = doRedirectToLoginPage(manager, requestParameters, iwc, realm);

        if (!goToLogin) {
          serverBean.setParameterList(null);
          serverBean.setServerUrl(null);
          serverBean.setDoRedirect(null);
          serverBean.setUsername(null);

          // interact with the user and obtain data needed to continue
          User user = iwc.getCurrentUser();
          String userSelectedClaimedId = getUserSelectedClaimedId(iwc, user);

          // --- process an authentication request ---
          AuthRequest authReq =
              AuthRequest.createAuthRequest(requestParameters, manager.getRealmVerifier());

          storeRequestedAttributesToSession(iwc, authReq);

          Boolean authenticatedAndApproved = isAuthenticatedAndApproved(iwc, user, authReq);

          String opLocalId = null;
          // if the user chose a different claimed_id than the one in request
          if (userSelectedClaimedId != null
              && !userSelectedClaimedId.equals(authReq.getClaimed())) {
            opLocalId = userSelectedClaimedId;
          }

          response =
              manager.authResponse(
                  requestParameters,
                  opLocalId,
                  userSelectedClaimedId,
                  authenticatedAndApproved.booleanValue(),
                  false); // Sign after we added extensions.

          if (response instanceof DirectError) {
            directResponse(resp, response.keyValueFormEncoding());
            return;
          } else if (response instanceof AuthFailure) {
            redirectToAuthorisationPage(req, resp, requestParameters, serverBean);
            return;
          } else {
            String[] extensionsToSign = prepareResponse(serverBean, response, iwc, user, authReq);
            boolean signExtensions =
                iwma.getSettings().getBoolean(OpenIDConstants.PROPERTY_SIGN_EXTENSIONS, false);

            AuthSuccess success = (AuthSuccess) response;
            if (signExtensions) {
              success.setSignExtensions(extensionsToSign);
            }

            // Sign the auth success message.
            // This is required as AuthSuccess.buildSignedList has a `todo' tag now.
            manager.sign(success);

            // caller will need to decide which of the following to use:

            // option1: GET HTTP-redirect to the return_to URL
            //		                cleanUpBeforeReturning(iwc, loginExpireHandle);
            // Clean up before returning
            serverBean.invalidate();

            getDAO().createLogEntry(user.getUniqueId(), realm, "");

            resp.sendRedirect(response.getDestinationUrl(true));
            return;

            // option2: HTML FORM Redirection
            // RequestDispatcher dispatcher =
            // getServletContext().getRequestDispatcher("formredirection.jsp");
            // httpReq.setAttribute("parameterMap", response.getParameterMap());
            // httpReq.setAttribute("destinationUrl", response.getDestinationUrl(false));
            // dispatcher.forward(request, response);
            // return null;
          }
        } else {
          redirectToLoginPage(req, resp, requestParameters, serverBean, manager);
          return;
        }
      } else if (OpenIDConstants.PARAMETER_CHECK_AUTHENTICATION.equals(mode)) {
        // --- processing a verification request ---
        response = manager.verify(requestParameters);
        responseText = response.keyValueFormEncoding();
      } else {
        // --- error response ---
        response = DirectError.createDirectError("Unknown request");
        responseText = response.keyValueFormEncoding();
        serverBean.invalidate();
      }
    } catch (MessageException me) {
      me.printStackTrace();
      responseText = me.getMessage();
      serverBean.invalidate();
    } catch (AssociationException ae) {
      ae.printStackTrace();
      responseText = ae.getMessage();
      serverBean.invalidate();
    } catch (ServerException se) {
      se.printStackTrace();
      responseText = se.getMessage();
      serverBean.invalidate();
    }

    // return the result to the user
    directResponse(resp, responseText);
  }
  @SuppressWarnings("unchecked")
  private void storeRequestedAttributesToSession(IWContext iwc, AuthRequest authReq) {
    if (authReq.hasExtension(AxMessage.OPENID_NS_AX)) {
      MessageExtension ext;
      try {
        ext = authReq.getExtension(AxMessage.OPENID_NS_AX);
        if (ext instanceof FetchRequest) {
          FetchRequest fetchReq = (FetchRequest) ext;
          OpenIDServerBean serverBean = ELUtil.getInstance().getBean("openIDServerBean");
          Map<String, String> allAttributes = (Map<String, String>) fetchReq.getAttributes();
          Map<String, String> required = (Map<String, String>) fetchReq.getAttributes(true);

          List<AuthorizedAttribute> allAttributesList = new ArrayList<AuthorizedAttribute>();
          List<AuthorizedAttribute> requiredAttributesList = new ArrayList<AuthorizedAttribute>();
          List<AuthorizedAttribute> optionalAttributesList = new ArrayList<AuthorizedAttribute>();

          String realm = serverBean.getRealm();

          for (String alias : allAttributes.keySet()) {
            ExchangeAttribute attribute =
                getDAO().getExchangeAttribute(alias, allAttributes.get(alias));
            if (attribute != null) {
              User user = iwc.getCurrentUser();
              AuthorizedAttribute aattr =
                  getDAO().getAuthorizedAttributes(user.getUniqueId(), realm, attribute);
              if (aattr == null) {
                aattr = new AuthorizedAttribute();
                aattr.setExchangeAttribute(attribute);
                aattr.setRealm(realm);
                aattr.setUserUUID(user.getUniqueId());
                aattr.setIsAllowed(true);
              }
              allAttributesList.add(aattr);
              if (required.containsKey(alias) && attribute.getType().equals(required.get(alias))) {
                requiredAttributesList.add(aattr);
              } else {
                optionalAttributesList.add(aattr);
              }
            } else {
              LOGGER.warning(
                  "Requesting unknown exchange attribute: "
                      + alias
                      + " : "
                      + allAttributes.get(alias));
              // throw new UnsupportedOperationException("Requesting unknown exchange attribute.");
            }
          }

          serverBean.setRequestedAttributes(allAttributesList);
          serverBean.setRequiredAttributes(requiredAttributesList);
          serverBean.setOptionalAttributes(optionalAttributesList);
          return;
        } else /*if (ext instanceof StoreRequest)*/ {
          // TODO implement?
          throw new UnsupportedOperationException("TODO");
        }
      } catch (MessageException e) {
        e.printStackTrace();
      }
    }
    if (authReq.hasExtension(SRegMessage.OPENID_NS_SREG11)) {
      try {
        MessageExtension ext = authReq.getExtension(SRegMessage.OPENID_NS_SREG11);

        if (ext instanceof SRegRequest) {
          SRegRequest sregReq = (SRegRequest) ext;
          List<String> all = sregReq.getAttributes();
          List<String> required = sregReq.getAttributes(true);
          List<String> optional = sregReq.getAttributes(false);

          List<AuthorizedAttribute> allAttributesList = new ArrayList<AuthorizedAttribute>();
          List<AuthorizedAttribute> requiredAttributesList = new ArrayList<AuthorizedAttribute>();
          List<AuthorizedAttribute> optionalAttributesList = new ArrayList<AuthorizedAttribute>();

          OpenIDServerBean serverBean = ELUtil.getInstance().getBean("openIDServerBean");
          String realm = serverBean.getRealm();
          User user = iwc.getCurrentUser();

          for (String alias : all) {
            ExchangeAttribute attribute = getDAO().getExchangeAttribute(alias);
            if (attribute != null) {
              AuthorizedAttribute aattr =
                  getDAO().getAuthorizedAttributes(user.getUniqueId(), realm, attribute);
              if (aattr == null) {
                aattr = new AuthorizedAttribute();
                aattr.setExchangeAttribute(attribute);
                aattr.setRealm(realm);
                aattr.setUserUUID(user.getUniqueId());
                aattr.setIsAllowed(true);
              }
              allAttributesList.add(aattr);
              if (required.contains(alias)) {
                requiredAttributesList.add(aattr);
              }
              if (optional.contains(alias)) {
                optionalAttributesList.add(aattr);
              }
            }
          }

          serverBean.setRequestedAttributes(allAttributesList);
          serverBean.setRequiredAttributes(requiredAttributesList);
          serverBean.setOptionalAttributes(optionalAttributesList);
          return;
        }
      } catch (MessageException e) {
        e.printStackTrace();
      }
    }
  }