This example demonstrates the simplified programming and packaging model changes provided in EJB 3.1. Since the mandatory use of Java interfaces has been removed in EJB 3.1, plain old Java objects can be annotated and used as EJB components. It also supports  the ability to place EJB components directly inside Web applications, thereby removing the need to produce archives to store the Web and EJB components and combine them together in an enterprise archive (EAR) file.