Actually, I am saying that the type parameter isn't actually used much.
Do you intend to support the semantics as I outlined? If so, then add the
type parameter.
On Sun, Nov 8, 2015 at 3:26 PM, Dmitry Kornilov <dmitry.kornilov_at_oracle.com>
wrote:
> Thanks for your answer. If similar methods exist in other frameworks (like
> Gson) users may want to have a similar functionality in the standard. So
> possibly it’s a good idea to keep them.
>
> Dmitry
>
> On 06 Nov 2015, at 19:15, Inderjeet Singh <inder_at_alumni.stanford.edu>
> wrote:
>
> This is how we did it in Gson. In the hindsight though, I will remove the
> extra type parameter from toJson().
>
> The only situation where it makes sense is when you want to limit the
> response to a base type. For example:
> class Sub extends Base {
> int a;
> }
> toJson(object, Base.class) omits the field "a".
>
> In practice, it is rare, and there or workarounds such as add a type
> adapter for Sub that limits the response to Base. Here is an example of
> such a type adapter:
> https://github.com/google-gson/typeadapters/blob/master/common/src/main/java/RestrictSerializationToBaseClassFactory.java
>
>
>
>
> On Fri, Nov 6, 2015 at 7:28 AM, <dmitry.kornilov_at_oracle.com> wrote:
>
>> Hi Experts,
>>
>> I am working on JSON-B reference implementation at the moment and want
>> to clarify one moment. We have three Jsonb::toJson(...) methods
>> accepting Type parameter:
>>
>> String toJson(Object object, Type runtimeType) throws JsonbException;
>> void toJson(Object object, Type runtimeType, Appendable appendable)
>> throws JsonbException;
>> void toJson(Object object, Type runtimeType, OutputStream stream)
>> throws JsonbException;
>>
>> I am not convinced why these methods are needed. Raw type is enough for
>> serialization. For deserialization this parameter is obviously
>> required.
>>
>> There is an example in DefaultMappingGenerics class which covers this
>> case (see below). It can be (and is) perfectly processed without
>> knowing a generic type. So this is a bad sample.
>>
>> List<java.util.Optional<String>> expected =
>> Arrays.asList(Optional.empty(), Optional.ofNullable("first"),
>> Optional.of("second"));
>> String json = jsonb.toJson(expected,
>> DefaultMappingGenerics.class.getField("listOfOptionalStringField").getG
>> enericType());
>> assertEquals("[null,\"first\",\"second\"]",json);
>>
>> Is there any real world sample showing that toJson(Object object) is
>> not enough and toJson(Object object, Type runtimeType) has to be used.
>>
>> Thanks,
>> Dmitry Kornilov
>>
>
>
>