how to give error message after validation of username and password

hello,
my problem looks like following.:

i have a login page and if user enters any wrong data which could not been matched with database then i have to give error message within same page by using jsp..give me suggestion please...!

Forward to the login page, with an error message added to the request by the login servlet.
On the login.jsp add a section to display this message if there is one in the request.