Simple Java field injection with Micronaut what's the missing step(s)?

Question

I am not sure yet if I'm on the wrong track or not. There is an example on the Micronaut Getting Started page for a V8 Engine and injecting a Vehicle.

• Defining Beans (often used Engine interface example)

With that example in mind. What is the most straightforward way to implement "Model A" with Micronaut using Java? If there's no direct approach, what is the closest hands-off method with Micronaut?

My simple vision of vanilla field injection stepping-on with such an example is as so (using Java), I'm labelling it "Model A" ...

Model A

  import io.micronaut.context.*

  public class MyApp {                        // (A)

      @Inject 
      Vehicle vehicle;


      public void runApp( String... args ){

         println( vehicle.start() )
      }

      public static main( String... args ){

          //   whatever set-up and steps need   // (B)
          //   for auto-inject / auto-wiring.

          MyApp body = new MyApp( args  );

          body.runApp();                       // (C)
      }
  }

Where the annotation processor uses provides an instance of the @Singleton Vehicle in this example. Or creates a new instance in the case of non-singleton-s.

Either way the result of the process would be that I don't need to write code to 'instantiate' the code or find a factory to do so explicitly.

The example itself goes on to demonstrate the method I'll label "Model B" (using Groovy)...

Model B

  import io.micronaut.context.*
    ...
  Vehicle vehicle = BeanContext.run().getBean(Vehicle)

  println( vehicle.start() )

Which in fact is MORE typing than just writing:

  Vehicle vehicle = new Vehicle();

      //    OR

  Vehicle vehicle = Vehicle.getInstance();

With some libraries you need to initialise the scopes or context, I see that. The question boils donw to what must I do to inject Vehicle as shown in my code.

I made a @Singleton and tried to @Inject the field. The reference is NULL. I then made a @Providerand set a break point. That isn't called.

• can I do "Model A"?
• If yes, what needs to happen?

I've scanned lots of examples doing great things. I'd love to get into those fancy things too. Right now I'm in the basement looking for a way up to the ground floor. Many thanks for you guidance.