AnnotationFormatterFactory should support @AliasFor [SPR-14844]

[spring-projects-issues]

Sebastian Davids opened SPR-14844 and commented

Pseudo code:

public @interface MyAnnotation {
   @AliasFor("alias")
   String value() default "";

   @AliasFor("value")
   String alias() default "not aliased";
}

public class Bean {
   @MyAnnotation("aliased")
   private String toBeAliased;
//...
}

public class MyAnnotationFormatterFactory implements AnnotationFormatterFactory<MyAnnotation> {

  public Printer<?> getPrinter(MyAnnotation annotation, Class<?> fieldType) {
      String alias = annotation.alias();
//...
}

Expectation would be alias to be "aliased" and not "not aliased".

---

Affects: 4.3.3

Issue Links:

• Support @Cache* as merged composed annotations [SPR-13475] #18054 Support @Cache* as merged composed annotations
• Differentiate between TypeDescriptors with same annotations but different attributes [SPR-13714] #18287 Differentiate between TypeDescriptors with same annotations but different attributes
• NoSuchMethodError when using AnnotatedElementAdapter with Java 7 [SPR-14872] #19438 NoSuchMethodError when using AnnotatedElementAdapter with Java 7
• ConversionService performance regression [SPR-14929] #19496 ConversionService performance regression
• Annotated method argument matching performance issue [SPR-15060] #19626 Annotated method argument matching performance issue
• Improve performance for conversions using a method parameter based type descriptor with annotations [SPR-14926] #19493 Improve performance for conversions using a method parameter based type descriptor with annotations

Referenced from: commits 62918ca, bf9083d

[spring-projects-issues]

Juergen Hoeller commented

Thanks for raising this! Indeed: an unfortunate limitation, originating from the legacy annotation support in TypeDescriptor. I've revised this towards our modern-day 4.3 facilities now, with formatting annotations now being equally capable (and following the same rules) as the general composable annotation model in Spring.

As a side note, there was a backwards compatibility concern with TypeDescriptor's legacy algorithm preferring inherited annotations over locally declared composed annotations. It turns out that this would only affect lookups on a Class whereas TypeDescriptor is only designed to work against fields and method parameters, so there was no reason to hold on to it.