Java SMTPSで認証・暗号化してメール送信(本文＋添付ファイル)

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.Date;
import java.util.Properties;
import javax.activation.DataHandler;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Store;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
import javax.mail.util.ByteArrayDataSource;

/**
 *
 * @author tool-taro.com
 */
public class SMTPSTest {

    public static void main(String[] args) throws MessagingException, IOException {

        String from = "差出人メールアドレス";
        String fromName = "差出人名を指定します";
        String subject = "件名を指定します";
        String to = "宛先メールアドレス";
        String toName = "宛名を指定します";
        String body = "これは本文です。\n\n\n\n\n\n\n\n\n\n以上。";
        String attachmentFileName = "添付ファイル名.txt";
        String attachmentFileType = "text/plain; charset=UTF-8";
        byte[] attachmentFileBody = "これは添付ファイルです。\n\n\n\n\n\n\n\n\n\n以上。".getBytes("UTF-8");

        String host = "メール送信サーバホスト";
        String user = "メール送信アカウント";
        String password = "メール送信アカウントパスワード";

        Properties properties;
        Session session;
        Store store = null;
        Transport transport = null;
        MimeMessage mimeMessage;
        MimeBodyPart messageBody;
        MimeMultipart multipart;
        InternetAddress[] address;

        try {
            properties = System.getProperties();
            properties.setProperty("mail.transport.protocol", "smtps");
            properties.setProperty("mail.smtp.port", "465");
            properties.setProperty("mail.smtp.auth", "true");
            properties.setProperty("mail.smtp.starttls.enable", "true");
            properties.setProperty("mail.smtp.starttls.required", "true");
            properties.setProperty("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
            properties.setProperty("mail.smtp.socketFactory.fallback", "true");

            session = Session.getInstance(properties);

            mimeMessage = new MimeMessage(session);
            //件名は(一応)JISで
            mimeMessage.setSubject(MimeUtility.encodeText(subject, "iso-2022-jp", "B"), "iso-2022-jp");
            mimeMessage.setSentDate(new Date());

            address = new InternetAddress[1];
            address[0] = new InternetAddress(from);
            //差出人名は設定しなくても問題ない
            if (fromName != null) {
                //差出人名は(一応)JISで
                address[0].setPersonal(MimeUtility.encodeText(fromName, "iso-2022-jp", "B"));
            }
            mimeMessage.setFrom(address[0]);

            address[0] = new InternetAddress(to);
            //宛名は設定しなくても問題ない
            if (toName != null) {
                //宛名は(一応)JISで
                address[0].setPersonal(MimeUtility.encodeText(toName, "iso-2022-jp", "B"));
            }
            mimeMessage.setRecipients(Message.RecipientType.TO, address);

            /*
                マルチパートのメッセージを作成する
                構造
                    パート1: 本文
                    パート2: 添付ファイル
             */
            multipart = new MimeMultipart();
            mimeMessage.setContent(multipart);

            //パート1: 本文
            messageBody = new MimeBodyPart();
            //本文のテキストは(一応)JISで
            messageBody.setText(body, "iso-2022-jp");
            messageBody.setHeader("Content-Transfer-Encoding", "7bit");
            multipart.addBodyPart(messageBody);

            //パート2: 添付ファイル
            messageBody = new MimeBodyPart();
            //添付ファイル名は(一応)JISで
            messageBody.setFileName(MimeUtility.encodeText(attachmentFileName, "iso-2022-jp", "B"));
            messageBody.setDataHandler(new DataHandler(new ByteArrayDataSource(new ByteArrayInputStream(attachmentFileBody), attachmentFileType)));
            multipart.addBodyPart(messageBody);

            transport = session.getTransport();
            transport.connect(host, user, password);
            transport.sendMessage(mimeMessage, mimeMessage.getAllRecipients());
        }
        finally {
            if (store != null) {
                try {
                    store.close();
                }
                catch (MessagingException e) {
                }
            }
            if (transport != null) {
                try {
                    transport.close();
                }
                catch (MessagingException e) {
                }
            }
        }
    }
}

$ javac SMTPSTest.java
$ java SMTPSTest