Question

以下Java代码用于将文件附加到电子邮件。我想通过电子邮件发送多个文件附件。任何建议将不胜感激。

public class SendMail {

    public SendMail() throws MessagingException {
        String host = "smtp.gmail.com";
        String Password = "mnmnn";
        String from = "xyz@gmail.com";
        String toAddress = "abc@gmail.com";
        String filename = "C:/Users/hp/Desktop/Write.txt";
        // Get system properties
        Properties props = System.getProperties();
        props.put("mail.smtp.host", host);
        props.put("mail.smtps.auth", "true");
        props.put("mail.smtp.starttls.enable", "true");
        Session session = Session.getInstance(props, null);

        MimeMessage message = new MimeMessage(session);
        message.setFrom(new InternetAddress(from));
        message.setRecipients(Message.RecipientType.TO, toAddress);
        message.setSubject("JavaMail Attachment");
        BodyPart messageBodyPart = new MimeBodyPart();
        messageBodyPart.setText("Here's the file");
        Multipart multipart = new MimeMultipart();
        multipart.addBodyPart(messageBodyPart);
        messageBodyPart = new MimeBodyPart();
        DataSource source = new FileDataSource(filename);
        messageBodyPart.setDataHandler(new DataHandler(source));
        messageBodyPart.setFileName(filename);
        multipart.addBodyPart(messageBodyPart);
        message.setContent(multipart);

        try {
            Transport tr = session.getTransport("smtps");
            tr.connect(host, from, Password);
            tr.sendMessage(message, message.getAllRecipients());
            System.out.println("Mail Sent Successfully");
            tr.close();
        } catch (SendFailedException sfe) {
            System.out.println(sfe);
        }
    }
}`

Answer 1

好吧，自从我完成JavaMail工作以来已经有一段时间了，但看起来您可以多次重复此代码：

DataSource source = new FileDataSource(filename);
messageBodyPart.setDataHandler(new DataHandler(source));
messageBodyPart.setFileName(filename);
multipart.addBodyPart(messageBodyPart);

例如，您可以编写一个方法来执行此操作：

private static void addAttachment(Multipart multipart, String filename)
{
    DataSource source = new FileDataSource(filename);
    BodyPart messageBodyPart = new MimeBodyPart();        
    messageBodyPart.setDataHandler(new DataHandler(source));
    messageBodyPart.setFileName(filename);
    multipart.addBodyPart(messageBodyPart);
}

然后从主代码中调用：

addAttachment(multipart, "file1.txt");
addAttachment(multipart, "file2.txt");

等

Answer 2

    Multipart mp = new MimeMultipart();

        MimeBodyPart mbp1 = new MimeBodyPart();
        mbp1.setContent(body,"text/html");
        mp.addBodyPart(mbp1);

        if(filename!=null)
        {
            MimeBodyPart mbp2 = null;
            FileDataSource fds =null;
            for(int counter=0;counter<filename.length;counter++)
            {
                mbp2 = null;
                fds =null;
                mbp2=new MimeBodyPart();
                fds = new FileDataSource(filename[counter]);
                mbp2.setDataHandler(new DataHandler(fds));
                mbp2.setFileName(fds.getName());
                mp.addBodyPart(mbp2);
            }
        }
        msg.setContent(mp);
        msg.setSentDate(new Date());
        Transport.send(msg);

Answer 3

现在（使用JavaMail 1.4），事情更简单：

messageBodyPart.attachFile(File file)

或：

messageBodyPart.attachFile（String filePath）

Answer 4

使用您要附加的第二个文件的文件名添加另一个块，并在message.setContent（multipart）命令之前插入它

    messageBodyPart = new MimeBodyPart();

    DataSource source = new FileDataSource(filename);

    messageBodyPart.setDataHandler(new DataHandler(source));

    messageBodyPart.setFileName(filename);

    multipart.addBodyPart(messageBodyPart);

Answer 5

只需向multipart添加更多文件。

Answer 6

拥有数组列表al，其中包含您需要邮寄的附件列表并使用下面给出的代码

for(int i=0;i<al.size();i++)
            {
                System.out.println(al.get(i));

                messageBodyPart = new MimeBodyPart();
                DataSource source = new FileDataSource((String)al.get(i));

                messageBodyPart.setDataHandler(new DataHandler(source));
                messageBodyPart.setFileName((String)al.get(i));
                multipart.addBodyPart(messageBodyPart);
                message.setContent(multipart);
            }

Answer 7

File f = new File(filepath);
File[] attachments = f.listFiles();
// Part two is attachment
for( int i = 0; i < attachments.length; i++ ) {
    if (attachments[i].isFile() && attachments[i].getName().startsWith("error"))  {
        messageBodyPart = new MimeBodyPart();
        FileDataSource fileDataSource =new FileDataSource(attachments[i]);
        messageBodyPart.setDataHandler(new DataHandler(fileDataSource));
        messageBodyPart.setFileName(attachments[i].getName());
        messageBodyPart.setContentID("<ARTHOS>");
        messageBodyPart.setDisposition(MimeBodyPart.INLINE);
        multipart.addBodyPart(messageBodyPart);
    }
}

Answer 8

 Multipart multipart = new MimeMultipart("mixed");

        for (int alen = 0; attlen < attachments.length; attlen++) 
        {

            MimeBodyPart messageAttachment = new MimeBodyPart();    
            fileName = ""+ attachments[attlen];


            messageAttachment.attachFile(fileName);
            messageAttachment.setFileName(attachment);
            multipart.addBodyPart(messageAttachment);

        }

Answer 9

Java Mail 1.3附加文件后更简单，

只需使用MimeBodyPart方法直接附加文件或从文件路径附加文件。

MimeBodyPart messageBodyPart = new MimeBodyPart();

//messageBodyPart.attachFile(String filePath);
messageBodyPart.attachFile(File file);

multipart.addBodyPart(messageBodyPart);

Answer 10

这是使用Spring 4 +

的100％

@RequestParam CommonsMultipartFile attachFile;
@RequestParam CommonsMultipartFile attachFile2;

Properties mailProperties = new Properties();
mailProperties.put("mail.smtp.auth", true);
mailProperties.put("mail.smtp.starttls.enable", true);
mailProperties.put("mail.smtp.ssl.enable", true);
mailProperties.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
mailProperties.put("mail.smtp.socketFactory.fallback", false);

JavaMailSenderImpl javaMailSenderImpl = new JavaMailSenderImpl();
javaMailSenderImpl.setJavaMailProperties(mailProperties);
javaMailSenderImpl.setHost("smtp.gmail.com");
javaMailSenderImpl.setPort(465);
javaMailSenderImpl.setProtocol("smtp");
javaMailSenderImpl.setUsername("*********@gmail.com");
javaMailSenderImpl.setPassword("*******");
javaMailSenderImpl.setDefaultEncoding("UTF-8");

List<CommonsMultipartFile> attachments = new ArrayList<>();
attachments.add(attachFile);
attachments.add(attachFile2);

javaMailSenderImpl.send(mimeMessage -> {

    MimeMessageHelper messageHelper = new MimeMessageHelper(mimeMessage, true, "UTF-8");
    messageHelper.setTo(emailTo);
    messageHelper.setSubject(subject);
    messageHelper.setText(message);

    if (!attachments.equals("")) {
        for (CommonsMultipartFile file : attachments) {
            messageHelper.addAttachment(file.getOriginalFilename(), file);
        }
    }
});

Answer 11

尝试使用此方法从数组中读取文件名

 MimeBodyPart messageBodyPart =  new MimeBodyPart();      
     Multipart multipart = new MimeMultipart();

     for(int i = 0 ; i < FilePath.length ; i++){
          info("Attching the file + "+ FilePath[i]);
          messageBodyPart.attachFile(FilePath[i]);
          multipart.addBodyPart(messageBodyPart);                       
     }         
 message.setContent(multipart);

Answer 12

我确实有更好的选择，可以在单个邮件中发送多个文件。 Mutipart类使我们可以轻松实现此功能。如果您可能没有任何相关信息，请从这里阅读：https://docs.oracle.com/javaee/6/api/javax/mail/Multipart.html

Multipart类为我们提供了两个具有相同参数的同名方法，这些方法的参数不同，即addBodyPart（BodyPart part）和addBodyPart（BodyPart part，int index）。对于一个文件，我们可以使用第一种方法，对于多个文件，我们可以使用第二种方法（带有两个参数）。

 MimeMessage message = new MimeMessage(session);
            Multipart multipart = new MimeMultipart();

            message.setFrom(new InternetAddress(username));

            for (String email : toEmails) {
                message.addRecipient(Message.RecipientType.BCC, new InternetAddress(email));
                }

                message.setSubject(subject);
                BodyPart messageBodyPart1 = new MimeBodyPart();
                messageBodyPart1.setText(typedMessage);

                multipart.addBodyPart(messageBodyPart1, i);
                i = i + 1;

                for (String filename : attachedFiles) {
                    MimeBodyPart messageBodyPart2 = new MimeBodyPart();


                    messageBodyPart2.attachFile(filename);

                    multipart.addBodyPart(messageBodyPart2, i);
                    i = i + 1;
                }

                message.setContent(multipart);
                Transport.send(message);

Answer 13

 for (String fileName: files) {
            MimeBodyPart messageAttachmentPart = new MimeBodyPart();
            messageAttachmentPart.attachFile(fileName);
            multipart.addBodyPart(messageAttachmentPart);
        }

您必须确保为每个附件创建一个新的 mimeBodyPart。该对象是通过引用传递的，所以如果你只这样做：

 MimeBodyPart messageAttachmentPart = new MimeBodyPart();
  
 for (String fileName: files) {
            messageAttachmentPart.attachFile(fileName);
            multipart.addBodyPart(messageAttachmentPart);
        }

它将附加相同的文件 X 次

@informatik01 在上面发布了一个答案，并附有指向文档的链接，其中有一个示例

如何使用JavaMail将多个文件附加到电子邮件？

13 个答案: