Java で HttpClient を使用して HTTP 基本認証を実行するにはどうすればよいですか?

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try {

            HttpClient client = new HttpClient();

            client.getParams().setAuthenticationPreemptive(true); // Add this line

            client.getState().setCredentials(
                    new AuthScope("ipaddress", 443, "realm"),
                    new UsernamePasswordCredentials("test1", "test1")
                    );

            PostMethod post = new PostMethod(
                    "http://address/test/login");

            post.setDoAuthentication( true );

            try {
                int status = client.executeMethod( post );
                System.out.println(status + "\n" + post.getResponseBodyAsString());
            } finally {
                // release any connection resources used by the method
                post.releaseConnection();
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        try {
            DefaultHttpClient httpclient = new DefaultHttpClient();

            httpclient.getCredentialsProvider().setCredentials(
                    new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT), 
                    new UsernamePasswordCredentials("test1", "test1"));

            // Add this line
            httpclient.setPreemptiveAuth(true); 

            HttpPost httppost = new HttpPost("http://host:post/test/login");

            System.out.println("executing request " + httppost.getRequestLine());
            HttpResponse response;
            response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();

            System.out.println("----------------------------------------");
            System.out.println(response.getStatusLine());
            if (entity != null) {
                System.out.println("Response content length: " + entity.getContentLength());
            }
            if (entity != null) {
                entity.consumeContent();
            }

            httpclient.getConnectionManager().shutdown();  
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
}

String encoding = Base64.getEncoder().encodeToString((user + ":" + pwd).getBytes());
HttpPost httpPost = new HttpPost("http://host:post/test/login");
httpPost.setHeader(HttpHeaders.AUTHORIZATION, "Basic " + encoding);

System.out.println("executing request " + httpPost.getRequestLine());
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();