Survey Java site deployable on Heroku

Develop a simple website that collects answers to questions, persisting them to a file. As each question is answered, the next should be presented to the user. When complete, you can simply show the responses selected by the user (a later version will transform the results). Will include a login page and they will only be able to see their data. If they log back in, they will again see their results. Code should be easy to maintain and properly layered (e.g. with a service and DAO layer). The work will be considered complete when it is running on Heroku and can be verified that it's persisting results to a file A good solution likely will lead to additional work Preferred technologies: Front end: Tomcat or Jetty, simple JS framework like JQuery. CSS framework preferred like Blueprint Framework: Spring Boot is acceptable but not required APIs: open source dependencies are ok