This is an example of server with Spring Boot + Spring Web Security + JPA (H2) + Thymeleaf + Bootstrap
In this repo you can find a server made with SpringBoot, you can see a login page make with Thymeleaf and apply themes and design with Twitter Bootstrap embedded in webjars, also we use fragments in Thymeleaf. To login, we use Spring Security Web, completely configure with annotations and doing use of H2-DB to store users, passwords and roles. To secure front and back, both, are using Expression-Based Access Control.