I added these lines to the file application.properties & then in that page (login page show below) i give the respective user-name and password. Then my page is showing..
spring.security.user.name=<your_username>
spring.security.user.password=<your_password>
spring.security.user.roles=USER,ADMIN
The Login Page is : https://i.sstatic.net/xFlFlvOi.png