Domain types serialization without depending on annotations from Jackson library.

[gusega]

Hi all,

I have my domain model and I don't want to make it depend on jackson annotations.

How do I enable json serialization for my model classes? Do I have to create POJOs for my domain types in the contexts where I want to serialize them or does jackson databind has some facilities to use instead? That is, to enable serialization at the call site.

Thanks.

[JooHyukKim]

@gusega More concrete explanation, preferrably with example would be helpful!

[gusega]

@cowtowncoder thanks a lot. For now the only thing that comes to mind that my domain classes otherwise dont need is factory methods and IgnoreUnknownProperties(true) annotations.

[cowtowncoder]

Ok that makes sense. Factory methods would probably need mix-in annotations; for IgnoreUnknownProperties there is the Global DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES if global defaulting works (not if only some types are to have lenient handling).

[gusega]

@cowtowncoder Thanks.
My understanding is that I create object mapper once for all application and then re-use it everywhere. So I cannot create different mappers for different serializations.

What is the recommended way of using jackson?

1. Create POJOs purely for serialization purposes and then convert from and to domain values after, or
2. Put annotations on the domain types making them serializable, or
3. Depends on the complexity of serialization

[cowtowncoder]

@gusega You can create differently configured ObjectWriters from ObjectMapper, so some customization is definitely possible (and ObjectReaders for deserialization). You can also create a small number of static ObjectMappers, not just one.

As to recommended way: it really depends on usage, users' situation -- we cannot and do not recommend one specific "true" approach. So I guess it's (3). So either (1) or (2) is fine; although TBH Jackson does not necessarily have many ways to accommodate (1).