The ForwardRoutingFilter looks for a URI in the exchange attribute ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR. If the URL has a forward scheme (such as forward:///localendpoint), it uses the Spring DispatcherHandler to handle the request. The path part of the request URL is overridden with the path in the forward URL. The unmodified original URL is appended to the list in the ServerWebExchangeUtils.GATEWAY_ORIGINAL_REQUEST_URL_ATTR attribute.