Doesn't Spring really support Interface injection at all?

Question

Hi

I know that Spring doesn't supports Interface injection and I've read that many a times.

But today as I came across an article about IOC by Martin Fowler (link), it seems using ApplicationContextAware in Spring is some what similar to the Interface injection.

when ever Spring' context reference is required in our Spring bean, we'll implement ApplicationContextAware and will implement the setApplicationContext(ApplicationContext context) method, and we'll include the bean in the config file. Is not this the same as Interface injection, where where telling the Spring to inject (or), say, pass the reference of the context into this bean?

Or I m missing something here? Thanks for any information!

ManiKanta

Answer 1

If you mean interface injection as defined on wikipedia, spring supports it out of the box for ResourceLoaders, ApplicationContexts, MessageSource, and others, with the interfaces ResourceLoaderAware, ApplicationContextAware, MessageSourceAware, respectively.

It is also possible to extend this mechanism with new interfaces an depedencies by registering a BeanPostProcessor.

The Spring reference manual explains this capability (and when one should (not) use it) quite clearly. BTW, I have generally found the spring reference manual to be much more reliable than what 'someone on the internet' says.