Auto-configure Hibernate with a JsonFormatMapper

[nosan]

#33870

[wilkinsona]

Thanks, @nosan.

Before merging this, we should consider if we want a way to disable it (an application property?) as it has the potential to be a breaking change.

[nosan]

Thanks, @wilkinsona
I was also thinking about this but I have not found a good name for it. Maybe spring.jpa.hibernate.auto-configure.json-format-mapper ?

[nosan]

I also used
properties.putIfAbsent in case someone already has registered they own JsonFormatMapper

[wilkinsona]

Thanks, @nosan. While looking for some inspiration for a property name, a couple of other things came to mind. I've noted them in a comment on 33870. I'll put this on hold for now until we've had a chance to figure those out.

[nosan]

Thanks, @wilkinsona. That makes sense.

What do you think about the following property format?

spring.jpa.hibernate.auto-configure.json-format-mapper=none
spring.jpa.hibernate.auto-configure.json-format-mapper=jackson
spring.jpa.hibernate.auto-configure.json-format-mapper=jsonb

By default, for example, jackson, as it is more popular.

[wilkinsona]

I'm not sure, unfortunately. I'm wondering if we need to widen the scope of the existing MVC-specific property and rename it to be more generally applicable. Let's keep that discussion to #33870 and then come back here once we're ready to update the proposal.