configOverrides(boolean.class) silently ignored, wheres .configOverride(Boolean.class) works for both primitives and boxed boolean values

[asaf-romano]

Using version 2.12:

mapper.configOverride(Boolean.class).setFormat(JsonFormat.Value.forShape(JsonFormat.Shape.NUMBER));

This works as expected. Boxed Boolean values are serialized as 1/0. Moreover, it also works for primitive booleans.

However,

mapper.configOverride(boolean.class).setFormat(JsonFormat.Value.forShape(JsonFormat.Shape.NUMBER));

seems to do nothing, for either types.

I find this behavior quite surprising. I think it's reasonable to assume any of the following:

1. boolean implies Boolean symmetrically
2. boolean implies Boolean, but not the other way around (mirroring the current behavior)
3. (1) + ability to override the format for the boxed type (to be clear, I've no use case for that)
4. An error to be thrown by configOverride.

[cowtowncoder]

Quick check: the usual way to refer to primitive boolean is Boolean.TYPE -- is it possible that boolean.class might refer to wrapper type (Boolean.class)?

If not, this does sound like a bug, and if so possibly simple one.

[cowtowncoder]

Ok, yes, I can reproduce this.

Before looking at the fix, this does cause a problem since the way this should work (as per design) is as per (3): Jackson does (or at least attempts :) to) distinguish between primitive and wrapper types; and so current behavior is incorrect. Problem here is that changing this now is API changing as the problem was not caught before 2.12.0 release.
As a result, I don't think I can change this in 2.12.x, as patches should not cause behavior change (although obv there is grey area wrt bug fixes).
I think I will do this for 2.13.0, however, since behavior is unintended and other configuration settings (for numbers, f.ex) do take into account primitive/wrapper distinction.

In theory I could try to specify defaulting of some sort (so that setting for Boolean would be default for boolean, but could further be overridden for boolean), but while that could be more compatible it would be different from handling of all types -- there should ideally be a general logic to primitive<-wrapper defaulting for all options. This does not exist, nor do I want to write one.

So. I think I'll work towards fixing this for 2.13.0.

[cowtowncoder]

The bug itself is simple; in BooleanSerializer.createContextual(), we have:

            JsonFormat.Value format = findFormatOverrides(serializers,
                    property, Boolean.class);

regardless of whether this is serializer for primitive or wrapper. Easy to fix in and of itself, but think I'll check to see how number serializers work. And perhaps even see how tricky defaulting might be; if simple enough, could add it only in here and remove from 3.0 (master).

[cowtowncoder]

Fixed for 2.13.0: I would recommend setting shape for both wrapper and primitive, even with 2.12, for future-proofing.

[asaf-romano]

wow, that was fast! Many thanks!

[cowtowncoder]

@asaf-romano sometimes this happens, but it is not necessarily representative of the typical bug report experience :) (obv. disclaimer).

That said, thank you for reporting this!