使javamail-1.4.2 傳送郵件時中文附件亂碼或顯示”??”的解決辦法

首先需要匯入的jar包 :

1. mail-1.4.1.jar 記得不是 javax.mail.jar

程式碼如下:

public class SendEmail {
    public static final String user = "[email protected]";// 傳送郵件郵箱
    public static final String pwd = "***************";// 傳送郵件郵箱密碼
    public static final String smtp = "smtp.163.com"
 
;// 簡單郵件傳輸協議
    public static void main(String[] args) {
        List<String> recipients = new ArrayList<String>();// 收件人列表
        String recipient = "[email protected]";// 收件人郵箱
        recipients.add(recipient);
        List<File> FileList = new ArrayList<File>();// 附件列表
        File file = new
 
 File("D:\\新建 360壓縮 ZIP 檔案.zip");
        FileList.add(file);
        String title = "郵件主題";
        String username = "傳送郵件人";
        String text = "郵件文字";
        try {
            Properties props = System.getProperties();
            props.put("mail.smtp.host", smtp);// 這裡預設使用163郵箱
            Session session = null
 
;
            if (user != null && pwd != null) {
                props.put("mail.smtp.auth", "true");
                props.put("mail.smtp.user", user);
                props.put("mail.smtp.password", pwd);

            } else {
                props.put("mail.smtp.auth", "false");
            }
            session = Session.getInstance(props, new javax.mail.Authenticator() {
                protected PasswordAuthentication getPasswordAuthentication() {
                    return new PasswordAuthentication(user, pwd);
                }
            });
            SMTPMessage message = new SMTPMessage(session);
            message.setSubject(title);
            message.setFrom(new InternetAddress(user, username));
            int receiverCount = recipients.size();
            if (receiverCount > 0) {
                InternetAddress[] address = new InternetAddress[receiverCount];
                for (int i = 0; i < receiverCount; i++) {
                    address[i] = new InternetAddress((String) recipients.get(i));
                }
                message.addRecipients(Message.RecipientType.TO, address);
            }

            MimeMultipart multi = new MimeMultipart();
            BodyPart textBodyPart = new MimeBodyPart();
            textBodyPart.setText(text);
            multi.addBodyPart(textBodyPart);
            if (FileList != null) {
                for (int i = 0; i < FileList.size(); i++) {
                    File f = (File) FileList.get(i);
                    FileDataSource fds = new FileDataSource(f);
                    BodyPart fileBodyPart = new MimeBodyPart();
                    fileBodyPart.setDataHandler(new DataHandler(fds));
                    fileBodyPart.setFileName(MimeUtility.encodeText(f.getName()));// 如果附件有中文通過轉換沒有問題了
                    multi.addBodyPart(fileBodyPart);
                }
            }
            message.setContent(multi);
            message.setSentDate(new Date());
            Transport.send(message);
            System.out.println("傳送成功！");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

最終效果如下 可正常顯示中文附件名稱

注意事項

1. 雖然 mail-1.4.1.jar 和 javax.mail.jar 這兩個包基本功能都一樣 , 但是使用後者時傳送附件總出現問題 ,我是測了半天才發現的這個問題 .
2. 以下程式碼要特別注意:
   fileBodyPart.setFileName(MimeUtility.encodeText(f.getName()));