Mixing Annotations with faces-config.xml Settings in JSF 2.0

With JavaServer Faces 2.0, we finally see the introduction of a standard, annotation based approach to component development. No longer do your JSF applications need to maintain a long and arduous faces-config.xml file. Instead, you can simply annotate your JavaBeans, and the JSF framework will manage your beans accordingly.

So, to have the JSF framework recognize a JavaBean, and manage the lifecycle of that instance, here’s how simple the annotation is:

And you can further annotate. So if you wanted the bean to be managed in the request scope, you simply add another annotation:

And all of this replaces the need for a faces-config.xml file such as the following:

Of course, the question always arises as to what happens if you both annotate the POJO, and you have a configuration in the faces-config.xml file. Well, at runtime, the faces-config.xml file trumps any annotations. So, if you have a bean whose behavior you want to change, but you can’t get in and edit the source code, all you have to do is configure a faces-config.xml file, and the corresponding settings will take precedence at runtime.