Outlook calendar appointment email with Java

This week I have been working on figuring out how to send an Outlook calendar appointment email with Java. I looked at a lot of different websites and it seemed like a lot of people are asking how to do this and no one is really giving any kind of solution. I use the web all of the time to answer questions, so I figured that since I had figured this out I would contribute back to the general knowledge base. Matt Bess also helped me in figuring this out.

What I have determined is that if you want to send an Outlook calendar appointment using Java, you have to send it as either a .vcs or .ics attachment. All the receipient has to do is double click on the attachment and it will be put in their calendar. Initially I wanted to have the behavior mimic that of a native Outlook appontment by giving the "Accept" or "Decline" buttons. Whenever I tried to send the email I would get the following error:

javax.activation.UnsupportedDataTypeException: no object DCH for MIME type text/calendar

This happens because there is not a mail handler defined in my mailcap file. But as far as I know there is not a java mail handler for Outlook messages. So the way to get around this problem is to send a multipart message. The first part is the content of the message that will display in the email client. This nice thing about doing it this way is that you can still have a HTML formatted email as the message and then attach the appointment for their calendar. Using the multipart gives a lot of flexibility. Here is some sample code:


MimeMessage message = mailSender.createMimeMessage();

message.setFrom( new InternetAddress("jared.blake@gmail.com", "jared.blake@gmail.com") );
javax.mail.Address address = new InternetAddress("jared.blake@gmail.com", "jared.blake@gmail.com");
message.addRecipient(MimeMessage.RecipientType.TO, address);
message.setSubject("test");

String contentType = "text/plain";

StringBuffer buffer = new StringBuffer();

buffer.append("BEGIN:VCALENDAR\n" +
  "PRODID:-//Microsoft Corporation//Outlook 11.0 MIMEDIR//EN\n" +
  "VERSION:1.0\n" +
  "BEGIN:VEVENT\n" +
  "ATTENDEE:MAILTO:jared.blake@gmail.com\n" +
  "DTSTART:20050120T170000Z\n" +
  "DTEND:20050120T180000Z\n" +
  "LOCATION;ENCODING=QUOTED-PRINTABLE:Lindon, UT\n" +
  "UID:040000008200E00074C5B7101A82E008000000004024D79F7EFDC4010000000000000000100\n" +
  " 00000CA06303EA8D5AD408E07455F234F0294\n" +
  "DESCRIPTION;ENCODING=QUOTED-PRINTABLE:This is a test calendar item.=0D=0A\n" +
  "SUMMARY;ENCODING=QUOTED-PRINTABLE:My Event\n" +
  "PRIORITY:3\n" +
  "END:VEVENT\n" +
  "END:VCALENDAR");

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

// Fill the message
messageBodyPart.setText("Here's the file");

// Create a Multipart
Multipart multipart = new MimeMultipart();

// Add part one
multipart.addBodyPart(messageBodyPart);

// Part two is attachment
// Create second body part
messageBodyPart = new MimeBodyPart();
String filename = "test calendar.vcs";
messageBodyPart.setFileName(filename);
messageBodyPart.setContent(buffer.toString(), "text/plain");

// Add part two
multipart.addBodyPart(messageBodyPart);

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

// send message
mailSender.send(message);


This code should give you a basic idea. You can find a lot of different sites that explain how to use the vCal format. I found this page to have some good links.

http://wmf.editthispage.com/discuss/msgReader$7900?mode=day

Like I said, I know a lot of people are looking to figure out how to send Outlook calendar appointments, so I hope this has helped get you started. If you have questions I will try to answer them the best I can.