private void handleRemoveFeedPost(Request request, HttpServletResponse httpServletResponse)
      throws Exception {
    LOG.info("removing feed");
    User user = userHelpers.getUser(request);

    try {
      if (user == null) {
        LOG.error("User not found");
        return;
      }

      String feedId = request.getParameter(PARAM_FEED_ID);

      LOG.info(String.format("Removing feed %s for user %s", feedId, user));

      // ttt1 add some validation; probably best try to actually get data, set the title, ...
      if (feedId == null || feedId.equals("")) {
        LOG.error("feed not specified");
        // ttt1 show some error
        return;
      }

      if (user.feedIds.remove(
          feedId)) { // ttt2 clean up the global feed table; that's probably better done if nobody
                     // accesses a feed for 3 months or so
        userDb.updateFeeds(user);
        LOG.info(String.format("Removed feed %s for user %s", feedId, user));
      } else {
        LOG.info(String.format("No feed found with ID %s for user %s", feedId, user));
      }
    } finally {
      httpServletResponse.sendRedirect(PATH_FEED_ADMIN);
    }
  }
  // !!! IDEA reports this as unused, but it is called from JSP
  public static FeedInfo getFeedInfo(String feedPath) {
    if (feedPath.startsWith(PATH_FEED + "/")) {
      try {
        if (feedPath.endsWith("/")) {
          feedPath = feedPath.substring(0, feedPath.length() - 1);
        }
        int k = PATH_FEED.length() + 1;
        int p = feedPath.indexOf('/', k);
        return p >= 0
            ? new FeedInfo(feedPath.substring(k, p), Integer.parseInt(feedPath.substring(p + 1)))
            : new FeedInfo(feedPath.substring(k), -1);
      } catch (Exception e) {
        LOG.error("Exception trying to parse the feed info", e);
      }
    }

    LOG.error("Invalid path from feed: " + feedPath);
    return new FeedInfo("INVALID", -1);
  }
  private void handleAddFeedPost(Request request, HttpServletResponse httpServletResponse)
      throws Exception {
    LOG.info("adding feed");
    User user = userHelpers.getUser(request);

    try {
      if (user == null) {
        LOG.error("User not found");
        return;
      }

      String url = request.getParameter(PARAM_NEW_FEED_URL);
      // ttt1 add some validation; probably best try to actually get data, set the title, ...
      if (url == null || url.equals("")) {
        LOG.error("New feed not specified");
        // ttt1 show some error
        return;
      }

      MessageDigest digest = MessageDigest.getInstance("MD5");
      String feedId = PrintUtils.byteArrayAsUrlString(digest.digest(url.getBytes("UTF-8")));
      feedId = feedId.substring(0, Config.getConfig().feedIdSize);

      Feed feed = feedDb.get(feedId);
      if (feed == null) {
        feed = new Feed(feedId, url);
        feedDb.add(feed);
      }

      if (user.feedIds.contains(feedId)) {
        LOG.error(String.format("Trying to add existing feed %s to user %s", feedId, user));
      } else {
        user.feedIds.add(feedId);
        userDb.updateFeeds(user);
      }
    } finally {
      httpServletResponse.sendRedirect(PATH_FEED_ADMIN);
    }
  }
  @Override
  public void doHandle(
      String target,
      Request request,
      HttpServletRequest httpServletRequest,
      HttpServletResponse httpServletResponse)
      throws IOException, ServletException {

    LOG.info("handling " + target);

    // !!! doHandle() is called twice for a request when using redirectiion, first time with
    // request.getPathInfo()
    // set to the URI and target set to the path, then with request.getPathInfo() set to null and
    // target set to the .jsp
    try {
      // request.setHandled(true);
      boolean secured;
      if (request.getScheme().equals("https")) {
        secured = true;
      } else if (request.getScheme().equals("http")) {
        secured = false;
      } else {
        httpServletResponse
            .getWriter()
            .println(
                String.format(
                    "<h1>Unknown scheme %s at %s</h1>",
                    request.getScheme(), request.getUri().getDecodedPath()));
        return;
      }

      if (request.getMethod().equals("GET")) {
        if (isInJar || target.endsWith(".jsp")) {
          // !!! when not in jar there's no need to do anything about params if it's not a .jsp,
          // as this will get called again for the corresponding .jsp
          if (prepareForJspGet(target, request, httpServletResponse, secured)) {
            return;
          }
        }
        if (target.startsWith(PATH_OPEN_ARTICLE)) {
          handleOpenArticle(request, httpServletResponse, target);
          return;
        }
        super.doHandle(target, request, httpServletRequest, httpServletResponse);
        LOG.info("handling of " + target + " went to super");

        // httpServletResponse.setDateHeader("Date", System.currentTimeMillis());     //ttt2 review
        // these, probably not use
        // httpServletResponse.setDateHeader("Expires", System.currentTimeMillis() + 60000);

        return;
      }

      if (request.getMethod().equals("POST")) {
        if (request.getUri().getDecodedPath().equals(PATH_LOGIN)) {
          handleLoginPost(request, httpServletResponse, secured);
        } else if (request.getUri().getDecodedPath().equals(PATH_SIGNUP)) {
          handleSignupPost(request, httpServletResponse);
        } else if (request.getUri().getDecodedPath().equals(PATH_CHANGE_PASSWORD)) {
          handleChangePasswordPost(request, httpServletResponse);
        } else if (request.getUri().getDecodedPath().equals(PATH_UPDATE_FEED_LIST)) {
          handleUpdateFeedListPost(request, httpServletResponse);
        } else if (request.getUri().getDecodedPath().equals(PATH_ADD_FEED)) {
          handleAddFeedPost(request, httpServletResponse);
        } else if (request.getUri().getDecodedPath().equals(PATH_REMOVE_FEED)) {
          handleRemoveFeedPost(request, httpServletResponse);
        } else if (request.getUri().getDecodedPath().equals(PATH_CHANGE_SETTINGS)) {
          handleChangeSettingsPost(request, httpServletResponse);
        }
      }

      /*{ // for tests only;
          httpServletResponse.getWriter().println(String.format("<h1>Unable to process request %s</h1>",
                  request.getUri().getDecodedPath()));
          request.setHandled(true);
      }*/
    } catch (Exception e) {
      LOG.error("Error processing request", e);
      try {
        // redirectToError(e.toString(), request, httpServletResponse); //!!! redirectToError leads
        // to infinite loop, probably related to
        // the fact that we get 2 calls for a regular request when redirecting
        httpServletResponse
            .getWriter()
            .println(
                String.format(
                    "<h1>Unable to process request %s</h1>", // ttt1 generate some HTML
                    request.getUri().getDecodedPath()));
        request.setHandled(true);
      } catch (Exception e1) {
        LOG.error("Error redirecting", e1);
      }
    }
  }