在使用JavaMail发送邮件一文中，记录了使用JavaMail发送普通文本给多个链接人。这里记录如何使用JavaMail发送带附件的邮件,只是在SendMail类中添加一个新的方法:

public void sendMail(List<String> recipients, String subject, String sendContent, List<String> filePaths)

recipients表示联系人列表，subject代表邮件主题，sendContent代表发送的邮件正文，filePaths代表添加为邮件附件的文件地址列表, 其代码如下:

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public void sendMail(List<String> recipients, String subject, String sendContent, List<String> filePaths) {
    try {
        MimeMessage mimeMessage = new MimeMessage(session);
        mimeMessage.setFrom(new InternetAddress(authenticator.getUsername()));
        mimeMessage.setSubject(subject);
        mimeMessage.setSentDate(new Date());
            
        final int num = recipients.size();
        InternetAddress[] addresses = new InternetAddress[num];
        for (int i = 0; i < num; i++) {
            addresses[i] = new InternetAddress(recipients.get(i));
        }
        mimeMessage.setRecipients(RecipientType.TO, addresses);
            
        MimeMultipart mimeMultipart = new MimeMultipart();
        MimeBodyPart mimeBodyPart = new MimeBodyPart();
        mimeBodyPart.setContent(sendContent, "text/html;charset=utf-8");
        mimeMultipart.addBodyPart(mimeBodyPart);
        for (String filePath : filePaths) {
            MimeBodyPart fileBodyPart = new MimeBodyPart();
            FileDataSource fds = new FileDataSource(filePath);
            fileBodyPart.setDataHandler(new DataHandler(fds));
                
            String fileName = MimeUtility.encodeText(fds.getName());
            fileBodyPart.setFileName(fileName);
            mimeMultipart.addBodyPart(fileBodyPart);
        }
        mimeMessage.setContent(mimeMultipart);
        Transport.send(mimeMessage);
    } catch (MessagingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

如上代码所示，发送带附件的邮件内容需要一个MimeMultipart对象作为容器，为每个附件或邮件正文创建一个MimeBodyPart对象，并将其添加到容器中。最后，将该容器分配到MimeMessage的发送内容中。代码24行使用encodeText方法是为了避免中文乱码的情况。