I want to send email just after user registering himself. Here is the scenario:

* User will submit sign up form
* Spring controller will accept the request, insert the data into db, send email to user.

The thing is user should get the successful sign up message instantly and the email sending process should also run in parallel but it should not affect sign up success response. i.e delay in email is accepted but sign up success message response should be delayed because of email process.