How can I find all beans with the custom annotation @Foo?

UPDATE: Spring 5.2 changed the behavior of context.getBeansWithAnnotation(...) and it now correctly handles beans created via factory methods. So simply use that.

Original answer

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While the accepted answer and Grzegorz's answer contain approaches that will work in all cases, I found a much much simpler one that worked equally well for the most common cases.

1. Meta-annotate @Foo with @Qualifier:

   @Target({ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER, ElementType.TYPE, ElementType.ANNOTATION_TYPE})
   @Retention(RetentionPolicy.RUNTIME)
   @Qualifier
   public @interface Foo {
   }
   

2. Sprinkle @Foo onto the factory methods, as described in the question:

   @Foo
   @Bean
   public IFooService service1() {
       return new SpecialFooServiceImpl();
   }
   

But it will also work on the type level:

@Foo
@Component
public class EvenMoreSpecialFooServiceImpl { ... }

3. Then, inject all the instances qualified by @Foo, regardless of their type and creation method:

   @Autowired
   @Foo
   List<Object> fooBeans; 
   

fooBeans will then contain all the instances produced by a @Foo-annotated method (as required in the question), or created from a discovered @Foo annotated class.

The list can additionally be filtered by type if needed:

@Autowired
@Foo
List<SpecialFooServiceImpl> fooBeans;

The good part is that it will not interfere with any other @Qualifier (meta)annotations on the methods, nor @Component and others on the type level. Nor does it enforce any particular name or type on the target beans.

Use getBeansWithAnnotation() method to get beans with annotation.

Map<String,Object> beans = applicationContext.getBeansWithAnnotation(Foo.class);

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