One nice feature that was in JDeveloper for a long time is the ability to automatically expose every component on your JSF page in a backing bean. While this is a nice "work saving" feature, you shouldn't be using this one in most cases.
The reason is that it will create objects in your backing bean code for a lot of items you don't actually need to manipulate, making your code bigger and more complex to maintain.
The right way of working is to expose only components you need in your backing bean - and JDeveloper makes this just as easy through the binding property in the property inspector and the edit option it has.
Here is a quick video showing you how to do that: