Add new methods in Deserializers, Serializers for new IterationType?

[cowtowncoder]

(see #3950 for background)

With 2.16 there's new IterationType which applies to types like Iterator and Stream. Callback interfaces Deserializers and Serializers should probably be extended to have separate callback methods, with default implementation that simply delegates to:

• Deserializers.findBeanDeserializer()
• Serializers.findSerializer()

[pjfanning]

My specific problem is here - https://github.com/FasterXML/jackson-module-scala/blob/b70b62eb1b04b345f6080391fbd3947652dd1fbe/src/main/scala/com/fasterxml/jackson/module/scala/ser/IteratorSerializerModule.scala#L67-L92

With findCollectionLikeSerializer, I am provided with elementTypeSerializer and elementSerializer. With findSerializer, I do not have these. The code seems to work with jackson-module-scala's basic Iterator tests but I'm concerned that I might not have enough coverage - that more complicated wrapped types (ie the type that the Iterator wraps - the T in Iterator<T>) will break because I don't the serializers for that type. Is there a way, I can find the serializers myself?

[cowtowncoder]

@pjfanning Good point, it'd be much more convenient to get (de)serializer passed in.

Yes, it is definitely possible to fetch (de)serializer(s) with given JavaType: bit easier for deserializers (since there is no runtime type), and bit more complex for serializers (since you may or may not have type when asked to construct serializer).

A good example of how to do this might be StreamSerializer:

https://github.com/FasterXML/jackson-modules-java8/blob/2.16/datatypes/src/main/java/com/fasterxml/jackson/datatype/jdk8/StreamSerializer.java

and Serializers impl that constructs it:

https://github.com/FasterXML/jackson-modules-java8/blob/2.16/datatypes/src/main/java/com/fasterxml/jackson/datatype/jdk8/Jdk8Serializers.java

although alternatively methods from BasicSerializerFactory or BeanSerializerFactory which call callbacks in Serializers could also work.