Hi Sergey,
>>> Why the MBR text does not refer to the Java parameter type as a primary key for sorting the providers, with the media type being the secondary keys.
>>
>> Of course MBRs do take into account the Java type, but there is no sorting as you point out.
>>
>> Suppose B extends A. If your resource parameter is of type B, there’s no point in using a MBR that can only produce A, you really need a B.
>
> And if an MBR B does not exist the MBR A can still return B
To help the discussion, let’s say B is ColorPoint and A is Point. If you have a MBR for Point (A), then how could it return a ColorPoint (B)? It would simply not know how to read the “color”. If it knew how to do that, it would be a MBR for ColorPoint.
> (example, Object-typed JAXB or JSON readers returning Object subclasses), I'm just adding the details, as opposed to disagreeing at this stage...
>
>> On the other hand, if your method returns B, you may be able to use a MBW for A if one for B does not exist —it will at least serialize a part of the object.
>>
>> By the same token, you could argue that if C extends B, then you could use a MBR for C to produce a B. So for readers you could use subtypes instead of supertypes. I don’t know the history if this, but I suppose readers were assumed to be strict (needing to deserialize complete objects) while writers were not.
>
> This is fine but this rule where a B MBR is obviously better than an A MBR does not hold if A MBR has a more specific media type.
>
> I feel there's something that needs to be improved/clarified here.
>
> Consider two cases below (in both cases a resource parameter is B extending A), with a POST text/plain body.
To be clear,
@POST
@Consumes(“text/plain")
void foo(B b) { … }
>
> Case1.
>
> @Consumes(*/*)
> MBR<A>
>
> and
>
> @Consumes(*/*)
> MBR<B>
>
>
> Obviously B wins - as you said it does not make sense to choose the A MBR if the B MBR exists.
>
>
> Case2.
>
> @Consumes(text/plain)
> MBR<A>
>
> and
>
> @Consumes(*/*)
> MBR<B>
>
>
> Suddenly MBR A wins ?
I’m not sure I follow. For MBRs we don’t sort by nearest superclass, right? Step 2 in 4.2.1 will only choose one that can produce a B. What am I missing?
Perhaps providing a complete example may help :)
— Santiago