I understand that it's used rarely. It's still questionable will it be
in the final spec or not. We will keep it there for now.
On 9.11.2015 00:53, Inderjeet Singh wrote:
> 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 <mailto: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 <mailto: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
>> <mailto: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
>>
>>
>
>