send the mail with attachment problem

Hi friends, i am using the below code now .Here filename has given directly so i don't want that way. i need to select the attached document from the jsp page(browser:<input type="file" name="upload"/>");How to get the file name


froString host = "192.168.10.205";
String from = "test@localhost";
String to = "komal@localhost";

// Get system properties
Properties properties = System.getProperties();

// Setup mail server
properties.setProperty("mail.smtp.host", host);

// Get the default Session object.
Session session = Session.getDefaultInstance(properties);

// Define message
Message message = new MimeMessage(session);
message.setFrom(new InternetAddress(from));
message.addRecipient(Message.RecipientType.TO,
new InternetAddress(to));
message.setSubject("JavaMail Attachment");

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

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

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

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

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

// Send the message
Transport.send(message);
System.out.println("Msg Send ....")