Java で HttpClient を使用した基本認証を実装するにはどうすればよいですか?

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.PostMethod;

...

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

...

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;

...

// Set authentication credentials
httpclient.getCredentialsProvider().setCredentials(
  new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT),
  new UsernamePasswordCredentials("test1", "test1")
);

...

// Create a Base64 encoded string for the credentials
String encoding = Base64.getEncoder().encodeToString((user + ":" + pwd).getBytes());

// Create the HTTP request with the correct header
HttpPost httpPost = new HttpPost("http://host:port/test/login");
httpPost.setHeader(HttpHeaders.AUTHORIZATION, "Basic " + encoding);

// Execute the request and handle the response accordingly
HttpResponse response = httpClient.execute(httpPost);