Why is @JsonTypeResolver separate from @JsonTypeInfo ?

It seems in JacksonAnnotationIntrospector that @JsonTypeResolver cannot exist without @JsonTypeInfo

protected TypeResolverBuilder<?> _findTypeResolver(MapperConfig<?> config,
            Annotated ann, JavaType baseType)
    {
...
JsonTypeInfo info = ann.getAnnotation(JsonTypeInfo.class);
JsonTypeResolver resAnn = ann.getAnnotation(JsonTypeResolver.class);
if (resAnn != null) {
            if (info == null) {
                return null;
            }

Unless I misunderstood this, I think it is unnecessary and confusing.

[bytesandwich]

Sorry for not explaining very well. When I read the javadoc, I thought typeResolver would generally be able to handle type information. Basically I thought it would should have the functionality required for #43. I was surprised when I looked at the unit tests and found that it relies on typeinfo.

As it does not exist without jsontypeinfo, I would think it logical to have an additional field in type info, and maybe rename type info, rather than adding this dependent second annotation. That way, the annotation encapsulates a logically complete unit of metadata.

I was thinking that if I use include Id.NONE then register a typeResolver to inspect the bean, I could get what I want. You suggested that TypeResolver wasn’t intended for this purpose, but I think it would be more intuitive to restructure these two annotations, particularly if things are being uprooted for #43.

[cowtowncoder]

I don’t thing we should change this interaction without specific reasons, as backwards compatibility with existing customizations is very important. Closing this for now; can re-open if revisiting is needed.