For maintaining session through hidden field, you have to maintain one hidden field.
First create a unique id on server side then set it to header(by using setHeader() method). Then you have to retrieve that id through javascript on each
jsp, maintain that Id with hidden filed , send that unique id to the server with hidden filed then match it on server side, if both ids are same then server knows that the request comes from the same user.Then server fulfill the request.
But its a traditional and complected ways. You can use more smarter way to maintain the session.
Hope, this will helpful to you.Thanks.