[jax-rs-spec users] [jsr339-experts] Re: Is ParamConverterProvider needed ?

From: Sergey Beryozkin <>
Date: Thu, 6 Sep 2012 15:47:17 +0100

Sorry, the user says "I use it for fetching domain objects from a
database using the primary key.", I missed that bit.
Still not seeing how the intermediate provider is helping,
sharing an example would make it much clearer

Cheers, Sergey
On 06/09/12 14:18, Sergey Beryozkin wrote:
> On 06/09/12 13:49, Marek Potociar wrote:
>> Please check the user comment in the corresponding issue for the
>> motivation:
> OK. The only question is then is whether we should introduce an
> indirection via the provider or have the extra parameters passed to
> ParamConverter, after a converter for a given class has been found ?
> May be it is OK, the way it is done now. The concern is that in order to
> address (IMHO) a very edge case (I've never had a single request for
> supporting subclasses during the custom parameter conversion, as opposed
> to the cases where we have XML payloads to be be bound to JAXB-managed
> classes) we have this indirection.
> I can not imagine the practical case. The user comment has a question
> mark: "Let's say you have an (abstract?) superclass with subclasses."
> It does not seem to work on the server side, given that no extra type
> info (like xsi:type in the XML payload) can be found in URI or header
> parameters
> Thanks, Sergey
>> Marek
>> On Sep 4, 2012, at 6:38 PM, Sergey Beryozkin <
>> <>> wrote:
>>> Hi
>>> We have ParamConverterProvider and ParamConverter, I wonder do we
>>> really need the former ?
>>> Example, individual ExceptionMapper implementations can be registered
>>> as providers, why should ParamConverter implementations be created
>>> indirectly via ParamConverterProvider ?
>>> I can see ParamConverterProvider allows to find the providers for
>>> arguments like "List<Book>" - but do we really need it ?
>>> Sergey