annotationprocessing101 | blog entry I have written about annotation processing

I am trying to learn about annotation processing by looking at this sample.

I've cloned it to my local machine and used IDEA to open it.

However IDEA tells me:

Project SDK not set up.

After setting up Java SDK, the project is not opening correctly. So how can I open this project?

The project structure :

I do not understand Java annotations with retention policy as RUNTIME that well. What I'm trying to do is create an annotation named @Authorize and use it on methods which needs user authorization in order to perform some action( the user is already authenticated at this point). eg. I have an order service with a getOrder() method. I want only the user who created this order to access it. `

I have a Spring REST controller with two endpoints that return a Foo and a Bar through their corresponding FooManager.handleFoo and BarManager.handleBar that contains the request handlers:

/MyService/foo

/MyService/bar

To be able to retrieve the correct Foo and Bar I need access to a GroupId for the calling user. The incoming request will contain the UserId. The UserId can then be used to make a back-end REST call to another service /OtherService/baz/{UserId} and the OtherService will return a GroupId for the given UserId.

Now I would like to "hide" the fetching of the GroupId since I need to feetch it for all resources that I return from my service. Preferrably I would like a small annotation that triggers the code that fetches the GroupId and that also returns a result. Something like: