Preciso fazer o get no WebClient , passando parametro json na url alguém por favor pra dar o help

String url =  (  "'{\"AUTENTICACAO\":{\"USUARIO\":\"SONAE\",\"SENHA\":\"Cns@Sonae#1902\"},\"GETPROG\":{\"DATAINI\":\"2018-07-05\",\"DATAFIN\":\"2018-07-08\",\"CODPRACA\":\"PLZ\"}}'") ;

        Disposable webClient = WebClient.create(vwsApiUrl + url )
                .method (  HttpMethod.GET)
                .uri ( vwsApiUrl + url )
                .contentType ( MediaType.APPLICATION_JSON_UTF8)
                .accept ( MediaType.APPLICATION_JSON_UTF8 )
                .exchange ()
                .flatMap ( clientResponse ->  clientResponse.bodyToMono ( String.class ) ).subscribe ( System.out::println );

        System.out.println ( webClient );
        }