The assignment is to generate autoresponse for new mails received in the mailserver. Every mail received should be responded with a reference number. But if the subject line contains a reference number then, autoresponse must not be generated for this mail. The problem is, i'm not able to check if the mail is a new mail or not. Checking the received date of the message is also not working.
The method message.getReceivedDate() is returning null.

How can i get the message received date. Why am i getting null for the getReceivedDate method