How to Send a Message on WhatsApp With Java

To send a message on WhatsApp with Java using the Twilio service, you need to create an account, obtain your account SID and auth token, then use these credentials to authenticate against the Twilio service. You also need to download the Twilio Java helper library and store it in a project directory. The Twilio WhatsApp sandbox allows you to test your application with your smartphone, where you can send a message using the join code provided by Twilio. Once authenticated, you can create a Java class that initializes the Twilio client using the account SID and auth token, creates a new message instance of the Message resource, sends a WhatsApp message to your personal phone number from your Twilio phone number, and prints the message SID for reference.