Spring ordered list of beans

Question

I have several beans that implement the same interface. Each bean is annotated with

@Component 
@Order(SORT_ORDER).
public class MyClass implements BeanInterface{
    ...
}

At one point I autowire a list of components and I expect a sorted list of beans. The list of beans is not sorted according the orders I have set with the annotation.

I tried implementing the interface Ordered and the same behaviour occurs.

@Component
public class Factory{


    @Autowired
    private List<BeanInterface> list; // <- I expect a sorted list here
    ...
}

Am I doing anything wrong?

Answer 1

Ordering autowired collections is supported since Spring 4.

See: Spring 4 Ordering Autowired Collections

Summary: if you add @Order(value=1), @Order(value=2)... to your bean definitions, they will be injected in a collection ordered according to the value parameter. This is not the same as declaring that you want the collection in natural order - for that you have to explicitly sort the list yourself after receiving it, as per Jordi P.S.'s answer.

Answer 2

I found a solution to the issue, as you say, this annotation is not meant for that despite it would be a nice feature.

To make it work this way its just necessary to add the following code in the bean containing the sorted list.

@PostConstruct
public void init() {
    Collections.sort(list,AnnotationAwareOrderComparator.INSTANCE);
}

Hope it helps.