Need special encoded characters in an Email subject with java 1.3.1_02

Question

I need to find a way to construct an Email through java with Subject lines built using characters from various Asian encodings. Such as Shift-JIS, Chinese Big5, etc.
These encodings cannot be in UTF-8 format and must remain in the native character set.
For testing I have an HTML file constructed using a single line of text with Shift-JIS characters. This file shows properly in web browsers under the Shift-JIS encoding view, and when used to create the body of an email it works perfectly through the DataHandler. However, I cannot get any java Reader to pull the same stream of characters into the Subject of the email. The Subject is always garbage no matter what I do.
Here is a small code sample with the relevant lines:
Session session = Session.getDefaultInstance(System.getProperties(), null);
MimeMessage reSend = new MimeMessage(session);
Transport ship = session.getTransport();
BufferedReader s = new BufferedReader(new InputStreamReader(new FileInputStream("C:\\JavaPrograms\\Converted\\JISConv.html"), "SJIS"));
String resub = s.readLine();
s.close();
reSend.setSubject(resub);
DataHandler collect = new DataHandler(new FileDataSource("C:\\JavaPrograms\\Converted\\JISConv.html"));
reSend.setDataHandler(collect);
ship.send(reSend);If I use the "SJIS" encoding in the InputStreamReader above, all characters are shown as "?". If I delete it entirely and use the system default, I get half of the characters and the rest are garbage. I can generate either of those results using various other Japanese and Western encoding definitions.
I have tried using the above code, also DataHandlers for the Subject, FileReader directly to a String, ByteArrayInputStreams, and StringBuffers. So far everything I try ends up at the same result.
Can anyone help me out? I really need this to work. If I can get this one encoding to work, then I should be able to program case switches for the other encodings.
Thanks kindly!
Kurt Jackson

Answer 1

First this is an issue with javamail and not with java.
What makes you think that the mime standard allows what you want to do?
Both of your 'tests' have been done using alternatives which do support alternative encodings.
These encodings cannot be in UTF-8 format and must remain in the native character set.That seems rather unlikely to me. Email is transported using one encoding. Certainly SMTP uses only ascii. So what ever you put in there is going to be ASCII no matter what you do to it. I suppose something at the end might try to read it using an alternative encoding but then what happens when someone really wants to send those ASCII characters?
Mime, I believe, is built on SMTP. And the subject line is still SMTP and thus ASCII.
Here is one link that covers mime (you might want to check the backing references though.)
http://www.mindspring.com/~mgrand/mime.html
I believe there is some sort of official or unofficial standard for doing what you want. I would suggest that you start by getting that first. I would suspect JavaMail doesn't support it.
Once you have a standard to follow you have the following choices..
- Modify JavaMail directly to support this (this then becomes a non-distributable solution.)
- Extend JavaMail do support this. This might or might not be possible.
- Write your own implementation (don't use JavaMail.)
- Find another solution from another source that already implements this.