ViaAuthenticator.java

package modern.challenge;

import java.io.IOException;
import java.net.Authenticator;
import java.net.PasswordAuthentication;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class ViaAuthenticator {

    public void authenticatorExample() throws IOException, InterruptedException {

        HttpClient client = HttpClient.newBuilder()
                .authenticator(new Authenticator() {
                    @Override
                    protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication(
                                "username",
                                "password".toCharArray());
                    }
                }).build();

        HttpRequest request = HttpRequest.newBuilder()
                // ...           
                .build();

        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
    }
}