Spring WS Client — Authentication using KeyStore/T

I have a Spring WS client that needs to authenticate using a keystore/trustore combination and also via basic auth.

This is the relevant Spring config that I currently have:

@Configuration
public class SpringWSConfig {
  @Bean
  public Jaxb2Marshaller jaxb2Marshaller() {
    Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
    marshaller.setPackagesToScan("io.shido.credit.domain");
    return marshaller;
  }

  @Bean
  public WebServiceTemplate webServiceTemplate() throws Exception {
    final WebServiceTemplate template = new WebServiceTemplate(jaxb2Marshaller(), jaxb2Marshaller());
    template.setDefaultUri("https://domain.tld/SVC/data");
    //template.setMessageSenders(new WebServiceMessageSender[]{ messageSender(), messageSender2() });
    //template.setInterceptors(new ClientInterceptor[] { wss4jSecurityInterceptor() });
    template.setMessageSender(messageSender());
    return template;
  }

  @Bean
  public HttpsUrlConnectionMessageSender messageSender() throws Exception {
    HttpsUrlConnectionMessageSender messageSender = new HttpsUrlConnectionMessageSender();
    messageSender.setTrustManagers(trustManagersFactoryBean().getObject()); // set the trust store(s)
    messageSender.setKeyManagers(keyManagersFactoryBean().getObject()); // set the key store(s)
    return messageSender;
  }

This works for the keystore/trustore part. I'm able to do the SSL handshake successfully, but right now I'm getting an HTTP 401 (Unauthorized). So I tried:

To have multiple senders; one of them HttpComponentsMessageSender with the username and password on it...but it doesn't work
To configure a ClientInterceptor with some Wss4jSecurityInterceptor config/settings...also doesn't work
To use a sender that inherits from HttpsUrlConnectionMessageSender, add a username and password fields, overwrite prepareConnection and set connection.setRequestProperty to use an Authorization header. This time I get an HTTP 405 (Method Not Allowed)

Any clues how to do this?

I ended up creating a new class and injecting it as a message sender in the Spring's WebServiceTemplate. That solves the HTTP 401 (Unauthorized) — don't quite remember about the HTTP 405 (Method Not Allowed).

@Bean
public HttpsUrlConnectionMessageSender messageSender() throws Exception {
  HttpsUrlConnectionMessageSender messageSender = new BasicAuthHttpsConnectionMessageSender(username, password);
  // ...
  return messageSender;
}

// You might need org.springframework.ws:spring-ws-support in order to
// have HttpsUrlConnectionMessageSender
public final class BasicAuthHttpsConnectionMessageSender extends HttpsUrlConnectionMessageSender {
  private String b64Creds;

  public BasicAuthHttpsConnectionMessageSender(String username, String password) {
    b64Creds = Base64.getUrlEncoder().encodeToString((username + ":" + password).getBytes(StandardCharsets.UTF_8));
  }

  @Override
  protected void prepareConnection(HttpURLConnection connection) throws IOException {
    connection.setRequestProperty(HttpHeaders.AUTHORIZATION, String.format("Basic %s", b64Creds));
    super.prepareConnection(connection);
  }
}

Refer to this answer also for more info. Both are related (if not almost the same).