code: public static synchronized void before(String url, HttpConsumer<Exchange> consumer) {
          checkStarted();
          instance().interceptors.add(new Interceptor(Interceptor.Type.BEFORE, HandlerUtil.parseUrl(url), consumer));
      }
docs: Adds an interceptor that executed right before the endpoint.
  Calling {@link Exchange#end()} or {@link Exchange#send(Object)} causes the request to complete.
  
  @param url      The URL pattern the interceptor will execute, only exact matches and wildcard (*) is allowed
  @param consumer The code to be executed when a URL matches the provided pattern