Setting @JsonProperty value through an @AliasFor in a custom meta-annotation

[raya-simeonova]

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Describe the bug

I am trying to use a custom meta-annotation with @AliasFor and @JacksonAnnotationsInside to alias the @JsonProperty annotation and set its value property through a field of my meta-annotation in a Spring Boot project. However, Jackson does not seem to recognize the alias and serialize the field with the specified name. I managed to achieve this through extending JacksonAnnotationIntrospector and overriding its method findNameForSerialization but I am wondering if there is a way to achieve this using the @AliasFor annotation, or if it is simply not supported.

Version Information

2.17.2

Reproduction

1. Define a custom annotation with @AliasFor and @JacksonAnnotationsInside to alias @JsonProperty.
2. Apply the custom annotation to a field in a class.
3. Serialize an instance of the class.

import com.fasterxml.jackson.annotation.JacksonAnnotationsInside;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.PropertyName;
import com.fasterxml.jackson.databind.introspect.Annotated;
import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;
import org.springframework.core.annotation.AliasFor;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

import java.lang.annotation.*;

class Scratch {
    public static void main(String[] args) throws JsonProcessingException {
        Param param = new Param();
        ObjectMapper objectMapper = Jackson2ObjectMapperBuilder.json().build();
        System.out.println(objectMapper.writeValueAsString(param));
    }

    @Target({ElementType.TYPE, ElementType.FIELD})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    @JacksonAnnotationsInside
    @JsonProperty
    public @interface ParamAnnotation {
        @AliasFor(annotation = JsonProperty.class, attribute = "value")
        String name() default "";
    }

    public static class Param {
        @ParamAnnotation(name = "firstName")
        public String surname = "Jackson";
    }
}

Expected behavior

The field surname should be serialized with the name firstName, meaning {"firstName":"Jackson"} is printed, but instead it is printed
{"surname ":"Jackson"}

Additional context

No response

[pjfanning]

We generally only accept jackson only problems. This problem includes Spring and some of your own annotation experimentation. I don't think it is appropriate to ask Jackson team to debug this for you. Can't you use ChatGPT or Stackoverflow and ask some colleagues to help?

[raya-simeonova]

I found on StackOverflow that the @AliasFor-like support is not available in Jackson, but that was a thread from 7 years ago. Therefore, I thought the Jackson team would be the most reliable source to confirm if that's still the case and if there is no support for it.

[cowtowncoder]

@JacksonAnnotationsInside handling is very simple: all it does is add other annotations of that type -- exactly as they are -- and uses them if it knows them (i.e. looks for known Jackson annotations). It does not have any translation logic, nor knowledge of 3rd party annotations.

For support for other 3rd party annotations (like Spring @AliasFor), custom AnnotationIntrospector functionality would be needed.

[raya-simeonova]

Thank you for the clarification! The custom AnnotationIntrospector has been working for me, I just wondered if there is another way.