The HTTP layer is made of the routes and controllers.Items components. The business layer is now made of two components, models.Shop and db.Schema (in Java, the latter component is hidden by JPA).

In this chapter, you saw how to write testing specifications for your web service, how to call your actions, supply them with fake HTTP requests, and process their results. You also saw how to integrate with relational database technologies. You learned that you can use the Play singleton to get a reference to the currently running application and, for instance, read its configuration settings. You learned how to hook into your application's life cycle using a global object. Finally, you saw how to start a fake application in your tests.

In the next chapter, you will see how to serve HTML pages and handle forms; your web service will evolve into a web application.