Java – MessagingExceptionIOException while sending message in java

jakarta-mailjava

I use the following code to send mail.Text message sending is working fine but Mail with attachment is not working it gives the Exception.How to solve this

javax.mail.MessagingException: IOException while sending message;
nested exception is:
javax.activation.UnsupportedDataTypeException: no object DCH for MIME type multipart/mixed;
boundary="—-=_Part_0_10430987.1294298904906"
at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:676)
at javax.mail.Transport.send0(Transport.java:189)
at javax.mail.Transport.send(Transport.java:118)
at Gmailer.GMailSender.sendMailAttach(GMailSender.java:114)
at SendMail.main(SendMail.java:22)
Caused by: javax.activation.UnsupportedDataTypeException: no object DCH for MIME type multipart/mixed;
boundary="—-=_Part_0_10430987.1294298904906"
at javax.activation.ObjectDataContentHandler.writeTo(Unknown Source)
at javax.activation.DataHandler.writeTo(Unknown Source)
at javax.mail.internet.MimeBodyPart.writeTo(MimeBodyPart.java:1403)
at javax.mail.internet.MimeMessage.writeTo(MimeMessage.java:1745)
at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:636)
… 4 more

Mail with Attachment code :

public synchronized void sendMailAttach(String subject, String body,
    String sender, String recipients)  {
try {
    MimeMessage message = new MimeMessage(session);

    message.setSender(new InternetAddress(sender));
    message.setSubject(subject);

    // Create the message part 
    BodyPart messageBodyPart = new MimeBodyPart();

    // Fill the message
    messageBodyPart.setText("hi Demo");

    Multipart multipart = new MimeMultipart();
    multipart.addBodyPart(messageBodyPart);

    // Part two is attachment
    messageBodyPart = new MimeBodyPart();
    String filename = "mail.txt";
    DataSource source = new FileDataSource(filename);
    messageBodyPart.setDataHandler(new DataHandler(source));
    messageBodyPart.setFileName(filename);
    multipart.addBodyPart(messageBodyPart);

    // Put parts in message
    message.setContent(multipart);

    if (recipients.indexOf(',') > 0)
        message.setRecipients(Message.RecipientType.TO,
                InternetAddress.parse(recipients));
    else
        message.setRecipient(Message.RecipientType.TO,
                new InternetAddress(recipients));
    Transport.send(message);

}
catch (MessagingException e) {
    System.out.println("MessagingException" + e.getMessage());
}
catch (Exception e) {
    System.out.println("Mail Send Exception " + e.getMessage());
}
 }

Text Mail send code:

public synchronized void sendMail(String subject, String body,
    String sender, String recipients) throws Exception {
try {
    MimeMessage message = new MimeMessage(session);
    DataHandler handler = new DataHandler(new ByteArrayDataSource(
            body.getBytes(), "text/plain"));
    message.setSender(new InternetAddress(sender));
    message.setSubject(subject);
    message.setDataHandler(handler);
    if (recipients.indexOf(',') > 0)
        message.setRecipients(Message.RecipientType.TO,
                InternetAddress.parse(recipients));
    else
        message.setRecipient(Message.RecipientType.TO,
                new InternetAddress(recipients));
    Transport.send(message);
} catch (Exception e) {

}
}

Best Answer

Firstly, you could make your code a little more concise by using MimeBodyPart.attachFile() instead of wrangling the DataSource/DataHandler code yourself.

Secondly, try setting the Content-Type and Content-Disposition headers on your attachment part with appropriate values. (attachFile will set the Content-Disposition for you by default.) For instance,

messageBodyPart = new MimeBodyPart();
messageBodyPart.attachFile(new File("mail.txt"));
messageBodyPart.setHeader("Content-Type", "text/plain; charset=\"us-ascii\"; name=\"mail.txt\"");

EDIT:

After thinking a bit, this has to be something amiss with class loading. Please check this other SO thread to see if it remedies your situation. (General issue: Probably an extra activation.jar in your classpath; a few other possibilities also thought to cause it.)

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