how i create notification system in jsp

Step 1 would be for you to design this or write your software design document. Many new programmers forget to sketch out what they want and proceed to code first. is an interesting read and if I was to tackle this my bet is it's more than one chunk of code but a design.

For example since the diagram there indicates you have a browser on the client, that would be in your spec as well.
That is, who said the notification was via web browser, email, text message or a phone call?