title: how to implement countdown trigger in server side using java?
body: <p>Bidding sites like quibids and ebay has a countdown showing how much time left for the auction. I know this can be taken care on FE and should be fairly easy. What I want to know is how to do this on server side? like sending an email to people participate but didn't win and updating database when times up. I've thought about two approaches to do this. </p>
  
  <ol>
  <li>keep the timer on client side and do updates when the first request hit</li>
  <li>open a new thread and make it sleep for x amount of time then wake up to do the updates.</li>
  </ol>
  
  <p>Both approaches don't sound right to me and will lead to issues I think. Like user will likely not getting the updates on time, or server will have lots of sleeping beauty waiting. </p>