Ignore enum case with JSON-B / Yasson

Question

Using JSON-B / Yasson is there any way to ignore case of enums when deserializing?

public class MyObject{
  MyEnum condition;
  //getters and setters
} 
public enum MyEnum{
 NEW, OLD, REFURBISHED;
}

part of incoming JSON: "condition" : "new" The problem is that the incoming JSON uses the enums in lowercase.

Answer 1

I don't thing this should be available out of the box. Because you technically can have both old and OLD as valid values of your enum living together, allowing for out-of-the-box uppercase conversion can break roundtrip equivalence. Think of serializing a MyEnum.old value to end up with a MyEnum.OLD value on deserialization.

You can however force such a behavior by using an adapter.

public static class MyAdapter implements JsonbAdapter<MyEnum, String> {

    @Override
    public String adaptToJson(MyEnum value) {
        return value.name();
    }

    @Override
    public MyEnum adaptFromJson(String s) {
        return MyEnum.valueOf(s.toUpperCase());
    }
}

Next, annotate the enum with @JsonbTypeAdapter.

@JsonbTypeAdapter(MyAdapter.class)
public enum MyEnum {
    NEW,
    OLD,
    REFURBISHED;
}

Alternatively, you create your Jsonb provider as follows.

Jsonb jsonb = JsonbBuilder.create(new JsonbConfig().withAdapters(new MyAdapter()));