Support deserialization of array field using elementwise addition method

[nmatt]

I have a third-party class for which I want to write a mixin. The class has collection-valued properties for which it has regular getters, but no collection-valued setters. Instead, it has "add" methods to add the collection elements one by one. E.g.:

    public Set<Foo> getFoos();
    public void addFoo(Foo foo);

It would be nice if some variant of @JsonProperty could be used on addFoo(Foo) to tell Jackson that, when deserializing foos, it should add the elements one by one using addFoo(Foo).

[cowtowncoder]

Ok, that is a possible addition.

But just in case, I'll mention that feature #1399 being added in 2.9 (2.9.0.pr1 is out) allows specifying properties to use "merge", like

    @JsonMerge(OptBoolean.TRUE)
    public Set<Foo> getFoos() { }

in which case add() method will be used to append entries to existing value, instead of default overwriting.
This works for different kinds of types; for POJOs it would avoid new instance construction, similarly for Map.

[nmatt]

Thanks, #1399 indeed is an alternative when the getter returns a modifiable reference to the internal state.

[cowtowncoder]

At this point, I have no plans to implement this feature, so closing.