Free app, Free Reference!!!!. This is a Java Enterprise Reference, gathering the java EE Annotations for developers who are using or learning Java EE.

Include :
Java Enterprise Edition 6: JPA 2, JSF 2.0 , EJB 3.1,
Spring Framework 3
Hibernate 3
ApectJ (Eclipse)
JUnit 4
Mockito
OpenXava
Struts 2

With annotations you will minimize the need for Xml descriptors and configurations . Use annotations for :

* Aspect Oriented Programming
* Object Oriented Programming
* Dependency injection.
* Timeouts
* Transactions
* Java Persistence Api Lifecycle
* Interceptors
* Object-Ralational Mapping
* Java Persistence Query Language or Native Query
* Java Server Faces (JSF) Management
* Test Drive Development
* Model View Controller
* Mocks
* Unit Test
* and so on