docs: public static String prependUri(String baseUri, String uri) {
          if (!uri.startsWith("/")) {
              uri = "/" + uri;
          }
          if (uri.length() == 1 && uri.charAt(0) == '/') {
              uri = "";
          }
          uri = baseUri + uri;
          return uri.replaceAll("[\\/]{2,}", "/");
      }