@Override
public String handleRequest(Object input, Context context) {
    try {
        // Azure AD OAuth2 token endpoint
        String tokenEndpoint = "https://login.microsoftonline.com/YOUR_TENANT_ID/oauth2/token";
        
        // Azure AD client ID and client secret
        String clientId = "YOUR_CLIENT_ID";
        String clientSecret = "YOUR_CLIENT_SECRET";

        // Load your SSL keystore
        KeyStore keystore = KeyStore.getInstance("JKS");
        InputStream keystoreInputStream = getClass().getResourceAsStream("/your-keystore.jks");
        String keystorePassword = "your_keystore_password"; // Change this to your keystore password
        keystore.load(keystoreInputStream, keystorePassword.toCharArray());

        // Create an SSLContext with the keystore
        X509Certificate certificate = (X509Certificate) keystore.getCertificate("your_certificate_alias");
        SSLContext sslContext = SSLContext.getInstance("TLS");
        sslContext.init(null, new X509Certificate[]{certificate}, null);

        // Set the custom SSLContext for HTTPS connections
        HttpsURLConnection.setDefaultSSLSocketFactory(sslContext.getSocketFactory());

        // Create an HTTP POST request to the token endpoint
        URL url = new URL(tokenEndpoint);
        HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
        connection.setRequestMethod("POST");
        connection.setDoOutput(true);

        // Add OAuth2 token request parameters
        String tokenRequestParams = "grant_type=client_credentials" +
                "&client_id=" + clientId +
                "&client_secret=" + clientSecret +
                "&scope=https://graph.microsoft.com/.default"; // Adjust the scope as needed

        // Write the token request parameters to the request body
        try (OutputStream os = connection.getOutputStream()) {
            byte[] inputBytes = tokenRequestParams.getBytes("UTF-8");
            os.write(inputBytes, 0, inputBytes.length);
        }

        // Read the response from the Azure AD token endpoint
        InputStream responseInputStream = connection.getInputStream();
        byte[] responseBytes = responseInputStream.readAllBytes();
        String response = new String(responseBytes);

        // Close the connection
        connection.disconnect();

        return response;
    } catch (Exception e) {
        // Handle exceptions appropriately in your Lambda function
        e.printStackTrace();
        return "Error: " + e.getMessage();
    }
}