Convention over configuration

Pursuing the idea of convention over configuration, further, enterprise applications can be developed without any initial configuration required. The APIs provide default behavior that matches the majority of use cases. Engineer are only required to put extra effort in if that behavior is not sufficient.

This implies that in today's world, enterprise projects can be set up with minimal configuration involved. The days of extensive XML configuration are over. Especially, applications that don't ship web frontend technology can keep XML files to a minimum.

Let's start with a simple example of an application that offers REST endpoints, and accesses databases and external systems. REST endpoints are integrated by JAX-RS that internally uses servlets to handle requests. Servlets traditionally are configured using the web.xml deployment descriptor file residing under WEB-INF. However, JAX-RS ships a shortcut by sub-classing Application, annotated with @ApplicationPath...