Will wait for the test cause I really don't see how "Jsonb handles such
event with creating instance of appropriate type" but wanted to share the
read before write solution works even if not elegant using the
typewrapper/adatper we spoke about:
public void ploymorphism() { // we run it since it checked list/item
conversion
final Bar bar = new Bar(); // ~your Animal
bar.value = 11;
final Bar2 bar2 = new Bar2();
bar2.value = 21;
bar2.value2 = 22;
final Polymorphism foo = new Polymorphism(); // the pojo with a collection
of bars
foo.bars = new ArrayList<>(asList(bar, bar2));
final Jsonb jsonb = JsonbBuilder.create(
new JsonbConfig()
.setProperty("johnzon.readAttributeBeforeWrite", true) // NOT STANDARD,
enforces to use the getter to determine the type to deserialize
.withPropertyOrderStrategy(PropertyOrderStrategy.LEXICOGRAPHICAL) /*
assertEquals() order */);
final String toString = jsonb.toJson(foo);
assertEquals("{\"bars\":[" +
"{\"type\":\"org.apache.johnzon.jsonb.AdapterTest$Bar\",\"value\":{\"value\"
:11}}," +
"{\"type\":\"org.apache.johnzon.jsonb.AdapterTest$Bar2\",\"value\":{\"value
\":21,\"value2\":22}}]}", toString);
final Polymorphism read = jsonb.fromJson(toString, Polymorphism.class);
assertEquals(2, read.bars.size());
assertEquals(11, read.bars.get(0).value);
assertTrue(Bar.class == read.bars.get(0).getClass());
assertEquals(21, read.bars.get(1).value);
assertTrue(Bar2.class == read.bars.get(1).getClass());
assertEquals(22, Bar2.class.cast(read.bars.get(1)).value2);
}
2016-03-23 14:18 GMT+01:00 Roman Grigoriadi <roman.grigoriadi_at_oracle.com>:
>
>
> On 03/23/2016 02:02 PM, Romain Manni-Bucau wrote:
>
>
>
> 2016-03-23 13:39 GMT+01:00 Roman Grigoriadi <roman.grigoriadi_at_oracle.com>:
>
>> I think [A] is misunderstood..
>>
>>
>>
>> *[A] Think I get it: the adapter will return Foo and then on this
>> instance Jsonb will populate fields. * That is not what I ment. An
>> adapter is at the end of the process, T instance is already populated both:
>> when adapter adapts it returns adapted result.
>> Above statement is maybe enough, but for sake of clarity let me revisit
>> whole process.
>>
>> 1. Lets have JSON document for a TypeWrapper<T>
>> {
>> "animal":{
>> "className":"com.foo.Dog",
>> "instance":{
>> "name":"Doggie",
>> "dogProperty":"Property of a Dog."
>> }
>> }
>> }
>>
>> During deserialization what happens first is a completed instance of a
>> TypeWrapper with a a fully populated T inside. This happens in following
>> steps:
>> 1. Jsonb encounters deserializing a TypeWrapper<T>, and processes it
>> custom TypeWrapperDeserializer.
>> 2. TypeWrapperDeserializer (implemented by us), creates an empty instance
>> of TypeWrapper.
>> 3. Jsonb reads and sets property "className" into TypeWrapper
>> 4. Jsonb loads a class by this classname and creates instance with
>> default construcotor in our case Dog or Cat and sets it to TypeWrapper
>> instance.
>>
>
> That's where I'm lost. Only way it could work - without putting this
> behavior in the spec - is if TypeWrapper overrides the setter of classname
> to also set the instance:
>
> public void setClassName(final String className) {
> this.className= className;
> try {
> this.value = Animal.class.cast(Thread.currentThread().getContextClassLoader().loadClass(className).newInstance());
> } catch (final InstantiationException | IllegalAccessException | ClassNotFoundException e) {
> throw new IllegalArgumentException(e);
> }
> }
>
> Nope, it is only the className set as a String in this moment.
> Next JsonParser enconters a JsonObject and pushes ObjectStarted event into
> JSONB. Jsonb handles such event with creating instance of appropriate type.
> That type is normally read from ClassModel (which is read from actual Field
> or ParameterizedType argument of a Collection). But in our case this type
> is swapped with a Class loaded dynamically by name.
>
So now we have a correct instance ready to be populated by common
> reflection deserialization.
>
> And then Jsonb before creating the Animal instance reads the field to
> extract its type which is likely not what is done since the type is deduced
> statically from the model class (field type) - this part is important to
> avoid surprises and open security issues.
>
> No need to create instance now, it is already fully populated. Just
> extract it from TypeWrapper as is.
>
>
> If I'm still wrong do you care writing a small test case showing that in
> action please?
>
> Sure I will implement a test and push it to our eclipselink git which
> hosts the jsonb-ri.
>
>
> 5. Jsonb parses a "ClassModel" for Dog or Cat class (reading all @Jsonb
>> annots etc if needed).
>> 6. Jsonb goes deeper in json document parsing json object for "instance"
>> property and populating all fields in Dog or Cat (doesn't really care what
>> is it as it is common reflection based process for all properties inside).
>> 7. After above is completed an instance of TypeWrapper with fully
>> deserialized T inside is passed to an adapter method "T
>> adaptFromJson(TypeWrapper<T> obj)".
>> 8. Result from adapter is than set to a field, setter, collection, map,
>> array or whatever else is declared in domain model to unmarshall into.
>>
>> What returns an adapter is already ready to be set into model as is with
>> polymorphism working this way.
>>
>> Now I suppose this is exactly what:
>> [A]....*"Thought adapter should return a populated instance otherwise no
>> way to convert to business model properly IMO"* means ?
>>
>> Hope this helps and will bring some light.
>>
>> Thanks,
>> Roman
>>
>>
>>
>> On 03/23/2016 12:49 PM, Romain Manni-Bucau wrote:
>>
>>
>> 2016-03-23 12:29 GMT+01:00 Roman Grigoriadi <
>> <roman.grigoriadi_at_oracle.com>roman.grigoriadi_at_oracle.com>:
>>
>>> You load a Dog or Cat class by name, which appears in json and
>>> instantiate it with default constructor. This is what I suppose a custom
>>> deserializer for TypeWrapper would do.
>>>
>>>
>> [A] Think I get it: the adapter will return Foo and then on this instance
>> Jsonb will populate fields. Thought adapter should return a populated
>> instance otherwise no way to convert to business model properly IMO (if you
>> don't have an explicit model you maybe don't want a setter or field to be
>> used). That's why I was kind of blocked there.
>>
>>
>>> If you want to polymorphically adapt each animal in a collection you
>>> would have instead annotate Animal.class with @JsonbTypeAdapter, or pass an
>>> instance of AnimalAdapter to JsonbConfig.
>>>
>>> You are right, you can't add @JsonbTypeAdapter(AnimalAdapter.class) to
>>> List<Animal> as it would than have to be declared as: "extends
>>> TypeAdapter<List<Animal>>" and parent implementation would not work than.
>>>
>>>
>> Well adapter for items instead of the field in case of a collection is
>> something we can implement - we do in Johnzon - and which is useful IMO.
>> That said it doesn't solve the polymorphism issue. If [A] is solved it can
>> work but today we don't have any way to know if the adapter builds the
>> instance or just instantiate it if I got you right.
>>
>>
>>> Did I get your point?
>>>
>>>
>> Think so.
>>
>>
>>> Roman.
>>>
>>>
>>> On 03/23/2016 12:04 PM, Romain Manni-Bucau wrote:
>>>
>>> I don't get this part "Jsonb looks at animal field model and gets
>>> "toType" from annotated adapter".
>>>
>>> How do you create a Dog in your example instead of an Animal.
>>>
>>> Keep in mind you don't know all types from jsonb point of view. The real
>>> use case is more obvious on a collection - at least for me:
>>>
>>> public static class Pojo {
>>> @JsonbTypeAdapter(AnimalAdapter.class)
>>> public Collection<Animal> animals; // Dog, Cow, Cat, Horse...
>>> }
>>>
>>>
>>>
>>> Romain Manni-Bucau
>>> @rmannibucau
>>> <http://www.tomitribe.com>http://www.tomitribe.com
>>> <http://rmannibucau.wordpress.com>http://rmannibucau.wordpress.com
>>> <https://github.com/rmannibucau>https://github.com/rmannibucau
>>>
>>> 2016-03-23 11:51 GMT+01:00 Roman Grigoriadi <
>>> <roman.grigoriadi_at_oracle.com>roman.grigoriadi_at_oracle.com>:
>>>
>>>> You don't instantiate X in adapter you already have it. Here is
>>>> implementation of such adapter:
>>>>
>>>> class TypeAdapter<T> implements JsonbAdapter<T, TypeWrapper<T>> {
>>>>
>>>> @Override
>>>> public TypeWrapper<T> adaptToJson(T obj) throws Exception {
>>>> TypeWrapper<T> wrapper = new TypeWrapper<>();
>>>> wrapper.setClassName(obj.getClass().getName());
>>>> wrapper.setInstance(obj);
>>>> return wrapper;
>>>> }
>>>>
>>>> @Override
>>>> public T adaptFromJson(TypeWrapper<T> obj) throws Exception {
>>>> return obj.getInstance();
>>>> }
>>>> }
>>>>
>>>> class AnimalAdapter extends TypeAdapter<Animal> {}
>>>>
>>>> Than you have a pojo like this:
>>>>
>>>> public static class Pojo {
>>>> @JsonbTypeAdapter(AnimalAdapter.class)
>>>> public Animal animal;
>>>> }
>>>>
>>>> And json like this:
>>>>
>>>> {
>>>> "animal":{"className":"com.foo.Dog",name":"Doggie","dogProperty":"Property of a Dog."}}
>>>> }
>>>>
>>>>
>>>> What happens during deserialization in our implementation is:
>>>> JsonParser generates an event for started object at "animal" property.
>>>> Jsonb looks at animal field model and gets "toType" from annotated adapter.
>>>> Deserialization than happens for TypedWrapper as for common arbitrary user
>>>> Type, but with custom deserializer, reading class property first and
>>>> creating instance from it. After TypedWrapper<Animal> is fully
>>>> deserialized, it is passed to adapter instance, to retrieve an Animal,
>>>> which is finally set to Animal field.
>>>>
>>>> Regards,
>>>> Roman
>>>>
>>>>
>>>> On 03/23/2016 11:20 AM, Romain Manni-Bucau wrote:
>>>>
>>>> Hi Roman,
>>>>
>>>> can you fill some "..." please? typically at the moment "I know the
>>>> type is X". How with an adapter do you instantiate X and then let jsonb
>>>> populate it (without having another Jsonb instance)? That was the main
>>>> missing part of the puzzle.
>>>>
>>>>
>>>> Romain Manni-Bucau
>>>> @rmannibucau
>>>> <http://www.tomitribe.com>http://www.tomitribe.com
>>>> <http://rmannibucau.wordpress.com>http://rmannibucau.wordpress.com
>>>> <https://github.com/rmannibucau>https://github.com/rmannibucau
>>>>
>>>> 2016-03-23 11:14 GMT+01:00 Roman Grigoriadi <
>>>> <roman.grigoriadi_at_oracle.com>roman.grigoriadi_at_oracle.com>:
>>>>
>>>>> Hi,
>>>>>
>>>>> @Romain - what you and Dmitry suggested with adapters, will actully
>>>>> work in our case. We will have to to add a custom deserializer handler for
>>>>> a "TypedWrapper<T>" (similar to collection / array or reflection
>>>>> deserializers), which will read a class property first and on
>>>>> encountering a json object for T will create a correct type instance. The
>>>>> only condition would be, that class property must appear before inner
>>>>> instance in json object for "TypedWrapper<T>" as Eugen suggested:
>>>>>
>>>>> {"classProperty":"com.foo.Dog","instance":{...}}
>>>>>
>>>>> Adapters will than work in a common way to extract T from TypedWrapper
>>>>> and set it to a class model be it a field or a collection/array.
>>>>>
>>>>> I would also add required enumeration of allowed subtypes into
>>>>> TypedAdapter:
>>>>>
>>>>> class TypedAdapter<T> implements JsonbAdapter<T, TypedWrapper<T>> {
>>>>> TypedAdapter(Class[] allowedSubtypes) {...}
>>>>> ...
>>>>> }
>>>>>
>>>>> So we don't allow loading of any arbitrary class suggested by incoming
>>>>> json in case of not trusted third party.
>>>>>
>>>>> @Romain - adding support for custom serializers / deserializers in
>>>>> fashion of fasterxml with access to JsonGenerator/JsonParser would also
>>>>> solve the problem in similar fashion, but it would be more complicated for
>>>>> a client to implement logic driven by JsonParser events, than by providing
>>>>> predefined adapter.
>>>>>
>>>>> Thanks,
>>>>> Roman
>>>>>
>>>>> On 03/21/2016 09:36 PM, Romain Manni-Bucau wrote:
>>>>>
>>>>> Hi Dmitry,
>>>>>
>>>>> was my thought as well but it doesn't really work cause in adapter you
>>>>> can't relaunch the deserialization chain with the same jsonb instance. The
>>>>> serialization side is the easy one but the deserialization makes adapters
>>>>> API not enough to have a consistent behavior accross the deserialization.
>>>>> Making the adapter "JsonbAware" would work. We can probably use @Inject
>>>>> (CDI if there or just the JSR 330 as an optional dependency if not)
>>>>>
>>>>> Side note: I'd like we enable this impl but we don't provide them in
>>>>> the spec since it is likely dependent on your use case and saw cases where
>>>>> type was not enough and we will likely not handle all possible models.
>>>>>
>>>>>
>>>>>
>>>>> Romain Manni-Bucau
>>>>> @rmannibucau
>>>>> <http://www.tomitribe.com>http://www.tomitribe.com
>>>>> <http://rmannibucau.wordpress.com>http://rmannibucau.wordpress.com
>>>>> <https://github.com/rmannibucau>https://github.com/rmannibucau
>>>>>
>>>>> 2016-03-21 21:27 GMT+01:00 Dmitry Kornilov <
>>>>> <dmitry.kornilov_at_oracle.com>dmitry.kornilov_at_oracle.com>:
>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> This topic has been discussed already. Current version of the spec is
>>>>>> clear about polymorphism: *“**Deserialization into polymorphic types
>>>>>> is not supported by default mapping. [JSB-3.8-1]”. *The spec is
>>>>>> almost finished and I am strongly against going back and changing some
>>>>>> basic things now.
>>>>>>
>>>>>> On the other hand I understand that this use case exists. There is a
>>>>>> possible workaround to it using adapters. Sorry if there are any mistakes,
>>>>>> I am writing code without checking.
>>>>>>
>>>>>> We can create a generic wrapper to any type holding its type info
>>>>>> like this:
>>>>>>
>>>>>> class TypedWrapper<T> {
>>>>>> String type;
>>>>>> T obj;
>>>>>> }
>>>>>>
>>>>>> We can create a generic adapter which converts type to wrapper and
>>>>>> vice versa. I am not putting a full implementation here, I hope that the
>>>>>> idea is clear:
>>>>>>
>>>>>> class TypedAdapter implements JsonbAdapter<T, TypedWrapper<T>> {
>>>>>> TypedWrapper adaptToJson(T obj) {
>>>>>> TypedWrapper<T> t = new TypedWrapper<T>();
>>>>>> t.type = obj.getClass().getName();
>>>>>> t.obj = obj;
>>>>>> return t;
>>>>>> }
>>>>>>
>>>>>> T adaptFromJson(TypedWrapper<T> t) {
>>>>>> // Use reflection API to create an instance of object based
>>>>>> on t.type field value
>>>>>> }
>>>>>> }
>>>>>>
>>>>>> Now lets imagine that we have the following classes:
>>>>>>
>>>>>> class Animal {
>>>>>> }
>>>>>>
>>>>>> class Dog extends Animal {
>>>>>> }
>>>>>>
>>>>>> class Cat extends Animal {
>>>>>> }
>>>>>>
>>>>>> class Foo {
>>>>>> Animal animal;
>>>>>> }
>>>>>>
>>>>>> To properly handle serialization/deserialization of Foo we just need
>>>>>> to create an adapter which extends TypedAdapter from above and annotate
>>>>>> *animal* field:
>>>>>>
>>>>>> class AnimalAdapter extends TypedAdapter<Animal,
>>>>>> TypedWrapper<Animal>> {
>>>>>> }
>>>>>>
>>>>>> class Foo {
>>>>>> @JsonbTypeAdapter(AnimalAdapter.class)
>>>>>> Animal animal;
>>>>>> }
>>>>>>
>>>>>> We can include TypedWrapper and TypedAdapter in reference
>>>>>> implementation.
>>>>>>
>>>>>> Thanks,
>>>>>> Dmitry
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 21 Mar 2016, at 19:31, Eugen Cepoi < <cepoi.eugen_at_gmail.com>
>>>>>> cepoi.eugen_at_gmail.com> wrote:
>>>>>>
>>>>>> Not sure if it should or not be part of jsonb. Though it is very
>>>>>> likely people will want that feature. On the other side, it is a good way
>>>>>> to have different impls distinguish them self by providing such advanced
>>>>>> features (I mean as part of the impl and not at all present in the spec).
>>>>>> In that case I would find it fine to have people configure directly the
>>>>>> impl api.
>>>>>>
>>>>>> When we think polymorphism, at first it seems enough to handle it
>>>>>> only for json objects, but it can also happen for other types, esp. ones
>>>>>> that are serialized as literals. Then where do you store the type? Same for
>>>>>> json arrays. This is just one aspect of the introduced complexity when one
>>>>>> wants to handle polymorphism. The produced json starts getting more and
>>>>>> more ugly.
>>>>>>
>>>>>> Then comes the moment when you want to change the name of the
>>>>>> serialized property or the format you use.
>>>>>>
>>>>>> In some other situations (depending on how it has been implemented)
>>>>>> you might want to have access to a dom structure that holds the properties
>>>>>> so you can extract from them what is related to the type and then "convert"
>>>>>> that structure to the target type. This happens if you allow the type
>>>>>> property to appear in any order.
>>>>>>
>>>>>> There are many other things that one could want for polymorphic
>>>>>> support which would make all that even more complex.
>>>>>>
>>>>>>
>>>>>> In genson I first handled it only for what gets serialized as a json
>>>>>> object and imposed that the type property must appear first in the json (so
>>>>>> we don't need to read the full structure before knowing the target type).
>>>>>> Then recently I added support for all types (literal and array) by wrapping
>>>>>> them in a json object (yeah not very nice, but has the merit of being
>>>>>> relatively simple).
>>>>>>
>>>>>>
>>>>>>
>>>>>> 2016-03-21 2:22 GMT-07:00 Sebastian Daschner <
>>>>>> <java_at_sebastian-daschner.de>java_at_sebastian-daschner.de>:
>>>>>>
>>>>>>> Hi guys,
>>>>>>>
>>>>>>> The idea was that this "javaType" (name is subject to change)
>>>>>>> wouldn't be included in all cases. Default behaviour should be to serialize
>>>>>>> as small / easy as possible. Only if the type information is needed to
>>>>>>> determine the actual type, an @JsonbTypeInfo annotation could be added to
>>>>>>> the corresponding type. Configuring a "forceTypeInfo" boolean for the
>>>>>>> programmatic JSONB config could be possible though.
>>>>>>>
>>>>>>> @Przemyslaw:
>>>>>>> Even if you solely use DTOs for serialization (I won't agree that
>>>>>>> that's a must for all situations) you can still have situations with
>>>>>>> subclasses and more complex hierarchies -- we had that case in several
>>>>>>> projects, also when using transfer objects to map the domain objects.
>>>>>>> "Flattening" the type hierarchies as workaround is not always desired.
>>>>>>>
>>>>>>> But the longer I think about your approach that enums could be used
>>>>>>> to derive the type information (like JPA, yes) the more I like this idea as
>>>>>>> it would be more generic (more difficult / more effort to configure, but
>>>>>>> easier to apply to different technologies). We should investigate further
>>>>>>> (with some examples) what approach could be the best fit for JSONB.
>>>>>>>
>>>>>>> But I highly recommend that some functionality to determine
>>>>>>> polymorphic types should be included in the spec.
>>>>>>>
>>>>>>>
>>>>>>> @Romain:
>>>>>>> The spec should in fact require the impl to check for "suitable"
>>>>>>> types then, i.e. only types to which the actual property type can be
>>>>>>> assigned to should be allowed, etc.
>>>>>>>
>>>>>>> I like your idea to add a "Wrapper" to unwrap instances but let
>>>>>>> JSONB still do the (de-)serialization. This could be helpful for more
>>>>>>> control how the containing type (the List in my example) should be
>>>>>>> instanciated. But it doesn't fully solve the polymorphism example in all
>>>>>>> cases, as the implementation of the actual type (Customer or VipCustomer)
>>>>>>> can still not determined from the nested JSON objects if there is no such
>>>>>>> thing as a JSON meta type information.
>>>>>>>
>>>>>>>
>>>>>>> Cheers,
>>>>>>> Sebastian
>>>>>>> On 03/21/2016 08:32 AM, Przemyslaw Bielicki wrote:
>>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> I'm not a fan of the original idea (and it's an euphemism). Remember
>>>>>>> that JSONB is used to serialize/deserialize DTOs, not domain objects. You
>>>>>>> should have an additional adapter layer to convert DTOs into application's
>>>>>>> business model/domain objects and back.
>>>>>>> Polymorphism is broken (yeah, it's another topic and more
>>>>>>> philosophic) and I would discourage its application in DTO layer. If you
>>>>>>> have to, you can use an enum to mark what's the target class (check JPA for
>>>>>>> additional inspirations). "//javaType": "x.y.z" is really bad idea IMO -
>>>>>>> what if you use the same JSON to communicate with applications developed in
>>>>>>> .net, python, php, c++ at the same time? (yes, it happens). Would you
>>>>>>> define a type for each platform?
>>>>>>>
>>>>>>> If you use DTOs in business layer, you're doing something wrong :)
>>>>>>>
>>>>>>> @Romain, your idea looks interesting, can you show and example or
>>>>>>> deserialization process where polymorphism is involved?
>>>>>>>
>>>>>>> Cheers,
>>>>>>> Przemyslaw
>>>>>>>
>>>>>>> On Sun, Mar 20, 2016 at 10:52 PM, Romain Manni-Bucau <
>>>>>>> <rmannibucau_at_tomitribe.com>rmannibucau_at_tomitribe.com> wrote:
>>>>>>>
>>>>>>>> Hi guys
>>>>>>>>
>>>>>>>> Why not allowing adapters to wrap and unwrap instances but keep
>>>>>>>> serializer mecanism. For serialization no issue but for deserialization we
>>>>>>>> need to switch the deserialized type and then post process the instance -
>>>>>>>> or do it automatically with an Unwrappable interface?
>>>>>>>>
>>>>>>>> Overall idea for this particular use case would be:
>>>>>>>>
>>>>>>>> X ----TypedWrapper(X)----> JSON
>>>>>>>> JSON----TypedWrapper.class----> TypedWrapped ----unwrap----> X
>>>>>>>>
>>>>>>>> Parts in arrows are adapter/jsonb integration.
>>>>>>>>
>>>>>>>> An alternative is to provide to adapters the stream and jsonp
>>>>>>>> instances to do it themself with probably a mapper reference to
>>>>>>>> re(de)serialise an object directly.
>>>>>>>>
>>>>>>>> Wdyt?
>>>>>>>> ---------- Message transféré ----------
>>>>>>>> De : "Romain Manni-Bucau" < <rmannibucau_at_tomitribe.com>
>>>>>>>> rmannibucau_at_tomitribe.com>
>>>>>>>> Date : 19 mars 2016 21:49
>>>>>>>> Objet : Re: [jsonb-spec users] Java polymorphism support
>>>>>>>> À : < <users_at_jsonb-spec.java.net>users_at_jsonb-spec.java.net>
>>>>>>>> Cc :
>>>>>>>>
>>>>>>>> Hi Sebastian
>>>>>>>>
>>>>>>>> I am not fan of that - Mark knows ;) - and in particular now I'm
>>>>>>>> sure we shouldnt do it: the 0-day vulnerability is still there and you open
>>>>>>>> the door to the same issue or a complicated config adding this feature in
>>>>>>>> something as generic as jsonb.
>>>>>>>> Le 19 mars 2016 21:28, "Sebastian Daschner" <
>>>>>>>> <java_at_sebastian-daschner.de>java_at_sebastian-daschner.de> a écrit :
>>>>>>>>
>>>>>>>>> Hi experts,
>>>>>>>>>
>>>>>>>>> I don't know whether this has been discussed in the mailing list
>>>>>>>>> before
>>>>>>>>> but a needed functionality would be to specify the Java type of
>>>>>>>>> properties in the serialized JSON.
>>>>>>>>>
>>>>>>>>> As JSON doesn't standardize comments or other "attributes" (like
>>>>>>>>> XML
>>>>>>>>> does) a "magic property" could be added.
>>>>>>>>>
>>>>>>>>> Please see the proposal (explored by Mark Struberg, Reinhard
>>>>>>>>> Sandtner
>>>>>>>>> and myself) on my blog:
>>>>>>>>>
>>>>>>>>> <https://blog.sebastian-daschner.com/entries/json_mapping_polymorphism_support>
>>>>>>>>> https://blog.sebastian-daschner.com/entries/json_mapping_polymorphism_support
>>>>>>>>>
>>>>>>>>> WDYT?
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Cheers,
>>>>>>>>> Sebastian
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
>