public String Login() {
    // login url
    String loginURL = baseURL+"/Login?username=admin&password=test&_spring_security_remember_me=true&submit=Login Name";
    // set headers
    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
    // create the request with headers
    HttpEntity<String> request = new HttpEntity<String>(headers);
    // get a new rest Template
    RestTemplate restTemplate = new RestTemplate();
    // call the url
    HttpEntity<String> response = restTemplate.exchange(loginURL, HttpMethod.POST, request, String.class);
    HttpHeaders headerResponse = response.getHeaders();
    // get the cookie
    cookie = headerResponse.getFirst(HttpHeaders.SET_COOKIE);
    return cookie;
}

@Test
public void TestLoginShouldReturnCookie1() {
stubFor(post(urlEqualTo(myURL+"/Login?username=admin&password=test&_spring_security_remember_me=true&submit=Login%20Name"))
        .willReturn(aResponse().withStatus(200))
        .withCookie("COOKIE", containing(REMEMBER_ME)));

String cookie = loginService.Login();

assertEquals(REMEMBER_ME, cookie);

}

14:27:10.488 [qtp878991463-70] ERROR WireMock - Request was not matched:

{
 "url" : "/Login?username=admin&password=test&_spring_security_remember_me=true&submit=Login%20Name",
 "absoluteUrl" : "http://localhost:8089/Login?username=admin&password=test&_spring_security_remember_me=true&submit=Login%20Name",
 "method" : "POST",
 "clientIp" : "127.0.0.1",
 "headers" : {
    "User-Agent" : "Java/1.8.0_101",
    "Connection" : "keep-alive",
    "Host" : "localhost:8089",
    "Accept" : "text/plain, application/json, application/*+json, */*",
    "Content-Length" : "0",
    "Content-Type" : "application/x-www-form-urlencoded"
  },
 "cookies" : { },
 "browserProxyRequest" : false,
 "loggedDate" : 1516544830458,
 "bodyAsBase64" : "",
 "body" : "",
 "loggedDateString" : "2018-01-21T14:27:10Z"
}
Closest match:
  {
    "url" : "http://localhost:8089/Login?username=admin&password=test&_spring_security_remember_me=true&submit=Login%20Name",
   "method" : "POST",
   "cookies" : {
   "COOKIE" : {
   "contains" :
   "FNROTlvZz09Onp0RmwwRnFqbHd2RXNFOFZiTWNaa"
   }
 }
}