Best Practise of injecting applicationContext in Spring3

Actually, both are bad. Both of them tie your application to the Spring framework, thus inverting the whole inversion-of-control concept. In an ideal world, your application should not be aware of being managed by an ApplicationContext at all.

Once you have chosen to violate this principle, it doesn't really matter how you do it. ApplicationContextAware is the legacy version that has been around at least since Version 2.0. @Autowired is a newer mechanism but they work in pretty much the same way. I'd probably go with ApplicationContextAware, because it semantically makes clear what it is about.

As @Sean Patrick Floyd says, the need of ApplicationContext is often due to a bad design. But sometimes you have no other option. In those cases I prefer the use of @Autowired because is the way I inject all other properties. So, if I use @Autowired for injecting MyRepository, why can't I use it for ApplicationContext or any other Spring bean?

I use Spring interfaces only for those things I can't do with annotations, for example BeanNameAware.

If you need to get a prototype in a singleton then you can use method injection. Basically, you create an abstract method that returns the object you need and spring will return the prototype everytime you call that method. You define the "lookup-method" in your spring config. Here are some links: http://docs.spring.io/spring/docs/1.2.9/reference/beans.html#beans-factory-method-injection http://java.dzone.com/articles/method-injection-spring