Support for overriding enum values with @JsonProperty or @JsonValue

[joschi]

This PR adds support for overriding enum values with the Jackson-specific annotations @JsonProperty or @JsonValue.

Those annotations allow customizing how enum values are serialized and deserialized by Jackson and this PR consolidates the generated OpenAPI specification with this customization.

Java example enums (both serializing and deserializing identically when using Jackson):

public enum SomeEnum {
  @JsonProperty("num-one")
  NUMONE,
	
  @JsonProperty("num-two")
  NUMTWO
}

public enum SomeEnum {
  NUMONE("num-one"), NUMTWO("num-two");

  private final String value;

  public SomeEnum(String value) {
    this.value = value;
  }

  @JsonValue
  public String getValue() {
    return value;
  }
}

Results in the generated OpenAPI specification:

someEnum:
  type: string
  enum:
    - num-one
    - num-two

Closes #3552

[jlous]

Need this! Please merge!

[joschi]

@frantuma Anything I can help you with for reviewing this PR?

[NicklasWallgren]

@frantuma @joschi
It might be a better idea to utilize findJsonValueAccessor from BeanDescriptor since it also supports JsonValue annotations specified in interfaces.

The current implementation fails on

public interface ApiEnum {
    @JsonValue
    String jsonValue();
}

public enum ResponseType implements ApiEnum {
    Http("http"),
    Websocket("websocket");

    private String description;

    ResponseType(String description) {
        this.description = description;
    }

    @Override
    public String jsonValue() {
        return description;
    }
}

while we're able to retrieve the actual jsonValueAccessor via

var typeFactory = TypeFactory.defaultInstance();
var type = typeFactory.constructFromCanonical(ResponseType.class.getCanonicalName());
var beanDesc = Json.mapper().getSerializationConfig().introspect(type);
var accessor = beanDesc.findJsonValueAccessor();