Send secure mail via Google with Java

import java.io.File;

import java.util.Properties;

import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;

import javax.mail.Authenticator;
import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;


public class Mail {
    public static void main(String[] args) {
        try {
            // No attachments
            //new Email().sendSimpleMail("Test from Java", "This email address is being protected from spambots. You need JavaScript enabled to view it.", "This email address is being protected from spambots. You need JavaScript enabled to view it.", "Testing...", null);
            // One attachment
            new Email().sendSimpleMail("This email address is being protected from spambots. You need JavaScript enabled to view it.",
                "password", "Test from Java", "This email address is being protected from spambots. You need JavaScript enabled to view it.",
                "This email address is being protected from spambots. You need JavaScript enabled to view it.", "Testing...",
                new String[] { "/tmp/Auth.java" });
        } catch (Throwable e) {
            e.printStackTrace();
        }
    }

    public static class Email {
        public void sendSimpleMail(String username, String password,
            String subject, String to, String from, String messageText,
            String[] attachmentPaths)
            throws AddressException, MessagingException {
            Properties mailProps = new Properties();
            mailProps.put("mail.transport.protocol", "smtp");
            mailProps.put("mail.smtp.starttls.enable", "true");
            mailProps.put("mail.smtp.host", "smtp.gmail.com");
            mailProps.put("mail.smtp.auth", "true");
            mailProps.put("mail.smtp.port", "465");
            //mailProps.put("mail.smtp.debug", "true");
            mailProps.put("mail.mime.charset", "UTF-8");
            mailProps.put("mail.smtp.socketFactory.port", "465");
            mailProps.put("mail.smtp.socketFactory.fallback", "false");
            mailProps.put("mail.smtp.socketFactory.class",
                "javax.net.ssl.SSLSocketFactory");

            Authenticator auth = new GMailAuthenticator(username, password);
            Session session = Session.getDefaultInstance(mailProps, auth);

            Message message = new MimeMessage(session);

            message.setFrom(new InternetAddress(from));
            message.setRecipient(Message.RecipientType.TO,
                new InternetAddress(to));

            message.setSubject(subject);

            // Prepare the content for message + possible attachments
            BodyPart messageBodyPart = new MimeBodyPart();
            messageBodyPart.setContent(messageText, "text/html");

            // Container for all parts, including at least message and possibly attachments
            Multipart multipart = new MimeMultipart();
            multipart.addBodyPart(messageBodyPart);

            for (int i = 0;
                    (attachmentPaths != null) && (i < attachmentPaths.length);
                    i++) {
                addAttachment(multipart, attachmentPaths[i]);
            }

            message.setContent(multipart);

            Transport.send(message);
        }

        private void addAttachment(Multipart multipart, String attachmentPath)
            throws MessagingException {
            MimeBodyPart attachmentPart = new MimeBodyPart();
            DataSource source = new FileDataSource(attachmentPath);
            attachmentPart.setDataHandler(new DataHandler(source));
            attachmentPart.setFileName(new File(attachmentPath).getName());
            multipart.addBodyPart(attachmentPart);
        }

        private class GMailAuthenticator extends Authenticator {
            private String username;
            private String password;

            public GMailAuthenticator(String username, String password) {
                this.username = username;
                this.password = password;
            }

            public PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication(username, password);
            }
        }
    }
}