To authenticate your Java application with the Graph API using client ID and secret without external dependencies, you'll need to implement the OAuth 2.0 authentication flow manually. Here's a basic example using Java's `HttpURLConnection`:
```java
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
public class GraphApiAuthentication {
public static void main(String[] args) {
// Replace these with your application registration details
String clientId = "your-client-id";
String clientSecret = "your-client-secret";
String tenantId = "your-tenant-id";
String accessToken = getAccessToken(clientId, clientSecret, tenantId);
System.out.println("Access Token: " + accessToken);
}
private static String getAccessToken(String clientId, String clientSecret, String tenantId) {
try {
// Azure AD token endpoint
String tokenEndpoint = "https://login.microsoftonline.com/" + tenantId + "/oauth2/v2.0/token";
// URL encode the client ID and client secret
String encodedClientId = URLEncoder.encode(clientId, StandardCharsets.UTF_8.toString());
String encodedClientSecret = URLEncoder.encode(clientSecret, StandardCharsets.UTF_8.toString());
// Create the HTTP connection
URL url = new URL(tokenEndpoint);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setDoOutput(true);
// Build the request payload
String payload = "grant_type=client_credentials" +
"&client_id=" + encodedClientId +
"&client_secret=" + encodedClientSecret +
"&scope=https://graph.microsoft.com/.default";
// Write the payload to the request
try (DataOutputStream wr = new DataOutputStream(connection.getOutputStream())) {
wr.writeBytes(payload);
wr.flush();
}
// Get the response
int responseCode = connection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
try (BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()))) {
StringBuilder response = new StringBuilder();
String inputLine;
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
// Parse the JSON response to extract the access token
// Note: Use a JSON library like Jackson or Gson for a production-level implementation
return response.toString();
}
} else {
System.out.println("Error getting access token. Response code: " + responseCode);
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
```
Replace `"your-client-id"`, `"your-client-secret"`, and `"your-tenant-id"` with your actual application registration details. This example uses the client credentials grant flow, and the access token is extracted from the response.
Note: This is a simplified example, and in a production environment, you should handle exceptions, manage token expiration, and enhance security. Additionally, consider using a JSON library for parsing the JSON response.
Regards,
Rushikesh VartakIf you find the response useful, kindly consider selecting
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