Why JacksonModule ignores JsonProperty annotations on enum members if at least one enum member does not have it?

[estroykov]

Hey, thanks for the great lib with good extension points!

I am having the following enum class:

public static enum Day {
   @JsonProperty("1")
   DAY_1,

   @JsonProperty("2")
   DAY_2,

   ...

   END;
}

So, not all enum members have @JsonProperty annotations and in this case it seems to be natural, because it's not possible to define enum member called 1, but it does not make much sense to put @JsonProperty("END") for END.

Then I use JacksonModule to generate a schema. If I had @JsonProperty annotation on END as well, then the schema would have been generated as follows:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "properties": {
    "r": {
      "type": "string",
      "enum": [
        "1",
        "2",
        "END"
      ]
    }
  },
  "required": [
    "r"
  ]
}

And this is fine. But if END does not have annotation, then the generated schema is:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "properties": {
    "r": {
      "type": "string",
      "enum": [
        "DAY_1",
        "DAY_2",
        "END"
      ]
    }
  },
  "required": [
    "r"
  ]
}

However, I would expect 1 and 2 instead of DAY_1 and DAY_2.

Looks like this is intended, see CustomEnumDefinitionProvider.getSerializedValuesFromJsonProperty(), which says explicitly that even at least one enum member does not have @JsonProperty annotation, then annotations on all other members are ignored.

In my case, I cannot modify the class, so in my case the only workaround is to add a custom module. But I am still wondering, why this case is not covered by JacksonModule.