Askar Ibragimov Askar Ibragimov - 1 month ago 14
Java Question

Spring: get all Beans of certain interface AND type

In my Spring Boot application, suppose I have interface in Java:

public interface MyFilter<E extends SomeDataInterface>


(a good example is Spring's public interface ApplicationListener< E extends ApplicationEvent > )

and I have couple of implementations like:

@Component
public class DesignatedFilter1 implements MyFilter<SpecificDataInterface>{...}

@Component
public class DesignatedFilter2 implements MyFilter<SpecificDataInterface>{...}

@Component
public class DesignatedFilter3 implements MyFilter<AnotherSpecificDataInterface>{...}


Then, in some object I am interested to utilize all filters that implement MyFilter< SpecificDataInterface > but NOT MyFilter< AnotherSpecificDataInterface >

What would be the syntax for this?

Answer

The following will inject every MyFilter instance that has a type that extends SpecificDataInterface as generic argument into the List.

@Autowired
private List<MyFilter<? extends SpecificDataInterface>> list;