Options Serializer

public class OptionsJson implements JsonDeserializer<Options>, JsonSerializer<Options> {

    @Override
    public EType deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
        return Options.getByKey(json.getAsJsonPrimitive().getAsString());
    }

    @Override
    public JsonElement serialize(Options src, Type typeOfSrc, JsonSerializationContext context) {
        return new JsonPrimitive(src.getKey());
    }

}