title: How to check email address is exists or not on server side in java
body: <p>I want to validate an email address in Java before sending an email.<br>
  That email address may exist on the server or not.</p>
  
  <p>How can I  test it?<br>
  I don't have any idea.</p>
  
  <p>Is there a way to check that a given email address exists on the server side?</p>