use @autowired in abstract base class

Question

As I know, field injection is not recommended. Should use constructor instead.

What I\'m trying to do here is using @Autowired in

Answer 1

The code that you provide won't compile. As long as in your base class you don't have the default constructor, you should call super(MyDemoService) in child.

Inherited(sub) class:

public class Sub extends Base {

    private final MySubService mySubService;

    @Autowired
    public Sub(MySubService mySubService, MyDemoService myDemoService){
        super(myDemoService);
        this.mySubService = mySubService;
    }
} 

Or, if MySubService is an implementation of MyDemoService

@Autowired
public Sub(MySubService mySubService){
    super(mySubService);
}

As long as your field MyDemoService myDemoService in abstract class is protected you can use it in subclasses.

If you have multiple implementation of MyDemoService, than you have to use @Qualifier as described in the answer that you have mentioned.

public Sub(@Qualifier("MySubService") MyDemoService mySubService){
    super(mySubService);
}