If the element complies than sufunction returns an empty string.Otherwise it returns a message describing the error and highlight appropriate element with yellow.
After user submission, the username and password filled parameters are passed to check file to apply a validation process.
If you run a validation of the users form input before the form is submitted, there will be no wait time and redundant load on the server.
Below, I explain each JSP step for the login process.
: This file contains the HTML login form written within the JSP tags.
Otherwise, the HTML login form will be printed out to the user. One for inserting the username and another for the password.