Support for @Order at the @Bean method level [SPR-11310]

[spring-projects-issues]

Shaozhen Ding opened SPR-11310 and commented

This won't order the wired list. Since AnnotationAwareOrderComparator only scan the Type annotations instead of Method annotations.

@Bean
@Order(2)
public Store getStore2(){
	return new Store();
}

@Bean
@Order(1)
public Store getStore1(){
	return new Store();
}

@Bean
    @Order(3)
public Store getStore3(){
	return new Store();
}

}

@Autowired
List<Store> stores;

---

Affects: 4.0 GA

Issue Links:

• Document common use cases for @Order vs @Priority vs @DependsOn [SPR-16213] #20761 Document common use cases for @Order vs @Priority vs @DependsOn

Referenced from: commits 001d0e7, c6d29f1

[spring-projects-issues]

Stéphane Nicoll commented

I understand the confusion but @Order has a specific note about this use case. In your case, you want a different priority for the same Class. Your Store class should implement org.springframework.core.Ordered so that you can set the order instance per instance, e.g.

@Bean
public Store getStore3() {
  return new Store(3);
}

Hope that helps.

[spring-projects-issues]

Juergen Hoeller commented

Indeed, this is a traditional @Order limitation. Ordering injected bean arrays and collections based on such order values is a new feature in 4.0 now, but basically inherits that AnnotationAwareOrderComparator limitation.

That said, with a little bit of extra context for the comparator, we should be able to respect @Order values on factory methods as well. Let's research this for 4.1.

Juergen

[spring-projects-issues]

Stéphane Nicoll commented

This is available on master in the next hour or so in 4.1.0.BUILD-SNAPSHOT for you to try.

Introduced OrderProvider and OrderProviderComparator, the latter allowing to sort a collection of elements according to a given OrderProvider instance.

In practice, we have a specific OrderProvider implementation that is able to retrieve the bean definition of a given value, checking on its factory method, if any, if an order has been specified. Such @Order declaration takes precedence and can be specified in a meta-annotation if necessary.