Adding `@Inject` to a resource method parameter causes the method to be invoked even if it does not match the request path or HTTP method about helidon HOT 5 CLOSED

(Not up to speed on any of the root causes, context, deeper issues, etc. but wanted to add this in case it is helpful.)

In any CDI application, if you put @Inject on a method, it becomes an initializer method with corresponding rules about its invocation by the CDI container. When you mix this with JAX-RS, it can be surprising for sure.

from helidon.

That could well explain what I'm seeing.

So maybe this is simply pilot error on my part in misusing/not understanding the implications of @Inject on methods. (I guess I'm used to seeing other annotations explicitly flagging init methods, like @PostConstruct).

I'll go back to my example and make sure that doing the @Inject on the constructor instead (and only there) works and, if so, I'll probably close this as PEBCAK.

from helidon.

This was definitely due to me misusing @Inject on the resource methods.

The GreetService constructor already has @Inject. I added a @ConfigProperty parameter to the constructor, saved the value in an instance field, and then changed the resource methods to use that and all is well.

from helidon.

Right; I mean the flow will be:

• {waves hands vaguely} a request comes into the JAX-RS implementation
• Jersey realizes a given resource has to be instantiated and delegates to the DI system in effect for that instantiation (the DI system is CDI in this case, not, say, HK2)
• CDI takes over the instantiation and follows its rules. One of those rules is to run initializer methods immediately after invoking the constructor.
• The resource class is now instantiated and Jersey resumes control and figures out what resource method to invoke, etc. etc.

from helidon.

Yes, that's all consistent with what I saw. The initial invocations of the methods with @Inject--as part of constructing the object--did see the correctly-injected config property. The later calls, responding to a request, did not. That matches up with your description, as does why it works to do the injection in the annotated constructor and store the values in instance fields.

from helidon.