Using Java 11’s HttpClient with Basic Authentication is straightforward. Below is an example of how to configure and send an HTTP request using Basic Authentication:

Steps:

1. Encode the Username and Password: Basic Authentication requires the credentials (username and password) to be Base64 encoded in the format username:password.
2. Set the Authorization Header: Attach the Base64 encoded value as an Authorization header in the request.
3. Use HttpClient to Send the Request: Use HttpClient to send the request to the desired endpoint.

Here’s an example implementation:

Example Code

package org.kodejava.net.http;

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.Base64;

public class HttpClientWithBasicAuth {
   public static void main(String[] args) throws Exception {
      // Define the username and password
      String username = "username";
      String password = "password";

      // Encode the credentials in Base64 format
      String auth = username + ":" + password;
      String encodedAuth = Base64.getEncoder().encodeToString(auth.getBytes());
      String authHeader = "Basic " + encodedAuth;

      // Create the HttpClient
      HttpClient client = HttpClient.newBuilder()
              .version(HttpClient.Version.HTTP_2)
              .build();

      // Create the HttpRequest with the Authorization header
      HttpRequest request = HttpRequest.newBuilder()
              .uri(URI.create("https://example.com/api/resource")) // Replace with your endpoint
              .header("Authorization", authHeader)
              .header("Content-Type", "application/json") // Optional, adjust if needed
              .GET() // Use POST, PUT, or DELETE if required
              .build();

      // Send the request and get the response
      HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());

      // Print the response details
      System.out.println("Status Code: " + response.statusCode());
      System.out.println("Response Body: " + response.body());
   }
}

Explanation

1. Base64 Encoding:
   • Concatenate the username and password using : as the separator.
   • Encode the concatenated string in Base64 format.
2. Authorization Header:
   • The Authorization header must include Basic followed by the Base64-encoded credentials.
3. HttpClient Configuration:
   • Use HttpClient.newBuilder() to configure HttpClient.
   • You can set the HTTP version with .version(HttpClient.Version.HTTP_2).
4. HttpRequest Building:
   • Use HttpRequest.newBuilder() to construct the request.
   • Attach the Authorization header to the HTTP request.
   • Specify the HTTP method (GET, POST, etc.).
5. Response Handling:
   • Use HttpResponse.BodyHandlers.ofString() to handle the response body as a String.

Output

If the credentials are correct, the HTTP server will process the request and return the desired response. Otherwise, the server will return HTTP 401 Unauthorized.

Notes:

• Replace `https://example.com/api/resource` with your actual endpoint.
• Ensure that the username and password are handled securely and are not hardcoded in production. Use secure configurations or credential storage mechanisms instead.
• Adjust the other headers (e.g., Content-Type) based on your API’s requirements.