Question

How to set an acknowledgement (like email or SMS) before JVM shuts down (this is on the server side, not client)?

Answer 1

You need to add a shutdown hook to the JVM, as described in the Runtime class:

If you wanted to print out a message when shutting down, you d do:

Runtime.getRuntime().addShutdownHook(new Thread() { public void run() {
  System.out.println("Goodbye, world!");
} } );

Obviously, fill in the goodbye world bit with what you want.

Answer 2

You may be able to use the Java Shutdown Hook mechanism for this.

Answer 3

I d recommend writing a Thread and adding it as a runtime hook. You can see examples here.