public static void main(final String[] args) {

    //Set up system property to not use subject cred and use login module in jaas.conf

    System.setProperty("javax.security.auth.useSubjectCredsOnly", "false");

    System.setProperty("java.security.auth.login.config", ProxytestApplication.class.getClassLoader().getResource("jaas.conf").getPath());

    //Optional, debug properties

    System.setProperty("sun.security.krb5.debug", "true");

    System.setProperty("sun.security.jgss.debug", "true");

    //Initialize credentials object

    Credentials use_jaas_creds = new Credentials() {

        public String getPassword() {

        return null;

        }

    public Principal getUserPrincipal() {

        return null;

        }

    };

    //Set up proxy for httpClient

    HttpHost proxy = new HttpHost( "<proxyhost>", <port>, "http" );

    //Setup use SPNEGO to authenticate to the proxy

    CredentialsProvider credsProvider = new BasicCredentialsProvider();

    credsProvider.setCredentials(new AuthScope(null, -1, null), use_jaas_creds);

    Registry<AuthSchemeProvider> authSchemeRegistry = RegistryBuilder.<AuthSchemeProvider>create().register(AuthSchemes.SPNEGO, new SPNegoSchemeFactory(true)).build();

    CloseableHttpClient httpclient = HttpClients.custom()

        // set our proxy - httpclient doesn't use ProxySelector

        .setRoutePlanner(new DefaultProxyRoutePlanner(proxy))

        .setDefaultAuthSchemeRegistry(authSchemeRegistry)

        .setDefaultCredentialsProvider(credsProvider).build();

    //Test

    HttpGet httpget = new HttpGet("https://examples.com");

    try {

        HttpResponse httpresponse = httpclient.execute(httpget);

        System.out.println(httpresponse);

    }   

    catch (IOException e) {

        e.printStackTrace();

    }

}