Sending email in Java using Smtp API

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class TurboSMTPMailExample {
    public static void main(String[] args) {
        try {
            // Specify the URL of the API endpoint
            URL url = new URL("https://api.turbo-smtp.com/api/v2/mail/send");

            // Specify Credentials
            String Consumerkey = "<CONSUMER_KEY>";
            String Consumersecret = "<CONSUMER_SECRET>";

            // Open a connection to the URL
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();

            // Set the request method to POST
            connection.setRequestMethod("GET");

            // Set the request headers
            connection.setRequestProperty("Content-Type", "application/json");
            connection.setRequestProperty("Accept", "application/json");
            connection.setRequestProperty("Consumerkey", Consumerkey);
            connection.setRequestProperty("Consumersecret", Consumersecret);

            // Enable input and output streams
            connection.setDoInput(true);
            connection.setDoOutput(true);

            // Define the request body (as JSON)
            //String requestBody = "{\"from\": \"user@example.com\", \"to\": \"user@example.com,user2@example.com\", \"subject\": \"This is a test message\"}";
            
            String requestBody = "{" +
                                "\"from\": \"user@example.com\", " +
                                "\"to\": \"user@example.com,user2@example.com\", " +
                                "\"subject\": \"This is a test message\", " +
                                "\"cc\": \"cc_user@example.com\", " +
                                "\"bcc\": \"bcc_user@example.com\", " +
                                "\"content\": \"Dear partner. We are delighted to invite you to an exclusive training session on UX Design. This session is designed to provide essential insights and practical strategies to enhance your skills.\", " +
                                "\"html_content\": \"Dear partner,<br />We are delighted to invite you to an exclusive training session on <strong>UX Design</strong>. This session is designed to provide essential insights and practical strategies to enhance your skills.\" " +
                                "}";            
            
            DataOutputStream outputStream = new DataOutputStream(connection.getOutputStream());
            outputStream.writeBytes(requestBody);
            outputStream.flush();
            outputStream.close();

            // Get the response code
            int responseCode = connection.getResponseCode();

            // Read the response from the server
            BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line;
            StringBuilder response = new StringBuilder();
            while ((line = reader.readLine()) != null) {
                response.append(line);
            }
            reader.close();

            // Print the response
            System.out.println("Response Code: " + responseCode);
            System.out.println("Response Body: " + response.toString());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}