如何在android中使用javamail api起草邮件？

import javax.mail.*;
import javax.mail.internet.*;

public class SendEmailActivity extends Activity {
    private static final String EMAIL_HOST = "smtp.exmail.qq.com";
    private static final String EMAIL_PORT = "465";
    private static final String EMAIL_USERNAME = "your_email@example.com";
    private static final String EMAIL_PASSWORD = "your_email_password";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_send_email);

        Button sendButton = findViewById(R.id.send_button);
        sendButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                sendEmail();
            }
        });
    }

    private void sendEmail() {
        Properties props = new Properties();
        props.put("mail.smtp.host", EMAIL_HOST);
        props.put("mail.smtp.port", EMAIL_PORT);
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.socketFactory.port", EMAIL_PORT);
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");

        Session session = Session.getInstance(props, new javax.mail.Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(EMAIL_USERNAME, EMAIL_PASSWORD);
            }
        });

        try {
            MimeMessage message = new MimeMessage(session);
            message.setFrom(new InternetAddress(EMAIL_USERNAME));
            message.addRecipient(Message.RecipientType.TO, new InternetAddress("recipient@example.com"));
            message.setSubject("This is the subject of the email");
            message.setText("This is the body of the email");

            Transport.send(message);
            Toast.makeText(getApplicationContext(), "Email sent successfully", Toast.LENGTH_SHORT).show();
        } catch (MessagingException e) {
            Toast.makeText(getApplicationContext(), "Failed to send email", Toast.LENGTH_SHORT).show();
            e.printStackTrace();
        }
    }
}