jackson-databind

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(note: migrated from https://github.com/FasterXML/jackson-core/issues/154 by @benson-basis)

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I was surprised to learn that Jackson will combine @JsonCreator with patching properties. Even, in particular, protected final properties. When I wrote a mixin with @JsonCreator, I thought that I was specifying the one and only way (give or take other annotated constructors) to construct the class.

I wish that there was an option to set that would have this effect, and throw rather than patch a property if the JsonCreator is not usable in a deserialization.

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My view of the semantics I want is

@JsonCreator(Complete = true)

If any @JsonCreator says this, then if Jackson feels a need to call a setter or patch a property, it should throw instead. For this to work, my other idea about JsonAnySetter versus JsonCreator has to be done, too.

FWIW, auto-detection of final fields may be already disabled by

objectMapper.disable(MapperFeature.ALLOW_FINAL_FIELDS_AS_MUTATORS);

so that final fields can be only used for reading values, but not modifying them.

But this still leaves the possibility of having non-final fields or setters. So I take the remaining problem being that of dropping all setters, including "any setter".