Not sure I fully got it but the idea was for vendors to provide an
extension api/module with an implementation of ParameterizedType: new
VendorParameterizedType<Map<String, MyPojo>>(Map.class, new Type[] {
String.class, Mypojo.class }) // or same using reflection to get the types
but it is slower and has some pitfalls as seen in CDI API.
If we can get such API (with auto or not discovery) in JSR 250 we are very
good IMO
Romain Manni-Bucau
@rmannibucau
http://www.tomitribe.com
http://rmannibucau.wordpress.com
https://github.com/rmannibucau
2016-04-27 15:18 GMT+02:00 Roman Grigoriadi <roman.grigoriadi_at_oracle.com>:
> Another preference to use such token is elimination of instance creation
> or extension. I thought that GenericType user may wish to deserialize into
> may be havy for instantiation in contrast to such token.
>
> For example what will you pass in method receiving Type for
> deserialization in a result of Map<String, MyPojo> ?
>
> Roman
>
>
> On 04/27/2016 03:08 PM, Romain Manni-Bucau wrote:
>
> Hi Roman,
>
> think we spoke about it and decided to not do it cause it was already
> everywhere with different API (JAXRS -
> <http://docs.oracle.com/javaee/7/api/javax/ws/rs/core/GenericType.html>
> http://docs.oracle.com/javaee/7/api/javax/ws/rs/core/GenericType.html,
> CDI -
> http://docs.oracle.com/javaee/7/api/javax/enterprise/util/TypeLiteral.html,
> ...) and using Type is enough. Issue is you loose the type safety with Type
> (guess that's why you ask).
>
> I know JSR 250 will get another release, would be awesome if we could get
> in touch with this spec (and maybe EE/CDI/JAXRS) to get a common annotation
> for that.
>
> If we can I'm clearly +1 otherwise I think implementations can provide
> this on top of Type until we get such an API.
>
> Does it make sense? I can ping CDI list about that if you want.
>
>
>
>
> Romain Manni-Bucau
> @rmannibucau
> http://www.tomitribe.com
> http://rmannibucau.wordpress.com
> https://github.com/rmannibucau
>
> 2016-04-27 14:57 GMT+02:00 Roman Grigoriadi <roman.grigoriadi_at_oracle.com>:
>
>> Hi experts,
>>
>> how about to include a class for holding info about generic types in API:
>>
>> public abstract class TypeInfo<T> {
>>
>> private final Type type; protected TypeInfo() {
>> //type extracted from <T>
>> } public Type getType() {
>> return type;
>> }
>> }
>>
>>
>> Such helper is present in Gson as TypeToken and in Jackson as
>> TypeReference.
>>
>> Jsonb methods with "Type runtimeType" argument will than be interchanged
>> with "TypeInfo runtimeTypeInfo" arg.
>> For example:
>>
>> <T> T fromJson(Reader reader, Type runtimeType)
>>
>> <T> T fromJson(Reader reader, TypeInfo<T> runtimeType)
>>
>>
>> Returning <T> instance in second case is type safe, and eliminates need
>> of creation anonymous class instance (or class extension) of (de)serialized
>> a Java type.
>> For example:
>>
>> List<MyPojo> result1 = jsonb.fromJson(jsonString, new TypeToken<List<MyPojo>>(){});
>>
>> instead of
>>
>> ArrayList<MyPojo>> result = jsonb.fromJson(jsonString, new ArrayList<MyPojo>>(){});
>>
>> WDYT? Thanks, Roman
>>
>
>
>