Using attachments with javamail

Question

Hi
I wonder if anyone could help me. Is is possible to send an (oracle)blob as an attachment using javamail? How would I go about doing this? Thanks in advance

Answer 1

You can attach arbitrary binary data to an email sent through javamail. How the recipient interprets that data depends on the mime type and on their email client. I think a mime type of application/octet-stream will result in a binary file for which the only option is saving to disk.
Below are code snippets from part of a program in which I deal with attachments. They are far from complete, but show all the important method calls.
import javax.mail.*;
import javax.mail.internet.*;
attachment = (NotifyInterface.Attachment)allData.getObject();
headers = new InternetHeaders();
headers.addHeader("Content-Type", attachment.getMimeType());
encodedData = base64Encode(attachment.getData());
mbpAttachment=new MimeBodyPart(headers, encodedData);
mbpAttachment.setFileName(attachment.getFileName());
mbpAttachment.setDisposition(MimeMessage.ATTACHMENT);
mbpAttachment.setHeader("Content-Transfer-Encoding", "base64");
byte[] base64Encode(byte[] rawData) throws MessagingException {
ByteArrayOutputStream bout = new ByteArrayOutputStream();
OutputStream out = MimeUtility.encode(bout, "base64");
try {
out.write(rawData);
out.close();
} catch(IOException e) {
throw (MessagingException)new MessagingException("Error encoding attachment").initCause(e);
return bout.toByteArray();
public static class Attachment implements Serializable {
String fileName;
String mimeType;
byte[] data;
public Attachment(String fileName, byte[] data, String mimeType) {
this.fileName = fileName;
this.data = data;
this.mimeType = mimeType;
public String getFileName() {
return fileName;
public String getMimeType() {
return mimeType;
public byte[] getData() {
return data;
public String toString() {
return "Attachment of type "+mimeType;