how to send HTML email

I have to send HTML file via email but not as attachment.

Message simpleMessage = new MimeMessage(mailSession);
try {
   fromAddress = new InternetAddress(from);
   toAddress = new InternetAddress(to);

} catch (AddressException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
}

try {
    simpleMessage.setFrom(fromAddress);
    simpleMessage.setRecipient(RecipientType.TO, toAddress);

    simpleMessage.setSubject(subject);
    simpleMessage.setText(text);

    Transport.send(simpleMessage);
} catch (MessagingException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

It is sending email simply with text message. I want to send HTML content which is stored in another file but not as attachment