ViaHeader.java

package modern.challenge;

import java.io.IOException;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.Base64;

public class ViaHeader {

    public void headerExample() throws IOException, InterruptedException {

        HttpClient client = HttpClient.newHttpClient();

        HttpRequest request = HttpRequest.newBuilder()
                .header("Authorization", basicAuth("username", "password"))
                // ...
                .build();

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

    private static String basicAuth(String username, String password) {
        return "Basic " + Base64.getEncoder().encodeToString((username + ":" + password).getBytes());
    }
}