docs: protected URI startServer() {
          try {
              server.start();
          } catch (Exception e) {
              throw new IllegalStateException("server start failed.", e);
          }
          final String uri = "http://" + server.getHost().getName() + ":" + port + contextPath;
          try {
              return new URI(uri);
          } catch (URISyntaxException e) {
              throw new IllegalStateException("Failed to create URI object: " + uri, e);
          }
      }