How to ignore only @JsonSerialize annotations in combination with DefaultTyping

Question

I have seen the many questions and answers about ignoring certain annotations, or even disabling all annotations:

.configure(MapperFeature.USE_ANNOTATIONS, false)

But

the first solution defeats DefaultTyping (types don't end up in the serialized JSON and
the second solution defeats many useful annotations, of which the most critical to us: java.beans.ConstructorProperties.

How can I ignore @JsonSerialize and still have typeinfo in my resulting JSON while still supporting other annotations such as ConstructorProperties?

Here's what I have so far:

private static ObjectMapper configureObjectMapper() {
    ObjectMapper mapper = new ObjectMapper();
    mapper.enableDefaultTyping(ObjectMapper.DefaultTyping.OBJECT_AND_NON_CONCRETE, JsonTypeInfo.As.PROPERTY);
    mapper.setAnnotationIntrospector(new JacksonAnnotationIntrospector() {
        @Override
        protected TypeResolverBuilder<?> _findTypeResolver(MapperConfig<?> config, Annotated ann, JavaType baseType) {
            if (ann.hasAnnotation(JsonSerialize.class) || ann.hasAnnotation(JsonDeserialize.class)) {
                return StdTypeResolverBuilder.noTypeInfoBuilder(); // or null
            }
            return super._findTypeResolver(config, ann, baseType);
        }
    });
    return mapper;
}
// or the same config using a JsonMapper builder

But this still processes @JsonSerialize for some reason. I'm on jackson 2.10.0.pr3.

The real problem I'm facing is that I'm serializing 3rd party objects, which contain provided @JsonSerialize for unrelated purposes, but without defining @JsonDeserialize. Even though they're perfectly serializable without these annotations, they end up blocking our deserialization. At the same time I don't know upfront which classes they are, so these should be encoded in the resulting JSON. Furthermore, some of these objects are generated with Lombok resulting in no-arg constructors annotated with java.beans.ConstructorProperties which Jackson can deal with fine under normal circumstances.

It's the above combination of configuration I'm not able to solve.

score 0 · Answer 1 · answered Nov 02 '19 at 11:18

Have you tried to override JacksonAnnotationIntrospector#findSerializer method:

class SkipSerializersJacksonAnnotationIntrospector extends JacksonAnnotationIntrospector {

    private final List<Class> classesToSkip = new ArrayList<>();

    public SkipSerializersJacksonAnnotationIntrospector() {
        classesToSkip.add(YourClass.class);
    }

    @Override
    public Object findSerializer(Annotated a) {
        if (classesToSkip.contains(a.getRawType())) {
            return null;
        }

        return super.findSerializer(a);
    }
}

It should allow you to skip JsonSerialize annotation and keep type.

How to ignore only @JsonSerialize annotations in combination with DefaultTyping

1 Answers1