Failed to convert argument [model] for value [null] due to: Cannot construct instance of `view.model.product.ProductViewModel`

Question

I am using Java 15 record feature with Micronaut 2.2.1, the serialization is not working

{
    "message": "Failed to convert argument [model] for value [null] due to: Cannot construct instance of `view.model.product.ProductViewModel` (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)\n at [Source: UNKNOWN; line: -1, column: -1]",
    "path": "/model",
    "_links": {
        "self": {
            "href": "/api/v1/product",
            "templated": false
        }
    }
}

ProductViewModel Record

public record ProductViewModel
        (
                @Nullable
                @JsonProperty("id")
                String id,

                @Nullable
                @JsonProperty("name")
                String name,

                @Nullable
                @JsonProperty("description")
                String description,

                @Nullable
                @JsonProperty("price")
                float price
        ) {
}

Controller

public Single<HttpResponse<?>> Create(@Body ProductViewModel model) {
        LOG.info(String.format("Controller --> Creating new product"));
        return iProductManager.Create(model).map(item -> HttpResponse.created(item));
    }

If I make that Float as well no difference in the serialization, same issue — San Jaisy, Dec 11 '20 at 16:11
do you have a default constructor for ProductViewModel class? the errors logs are saying that. — roottraveller, Dec 11 '20 at 16:14
@roottraveller ProductViewModel is not a class it is a record. I am using java 15 preview feature. — San Jaisy, Dec 11 '20 at 16:15
does this help https://stackoverflow.com/questions/53191468/no-creators-like-default-construct-exist-cannot-deserialize-from-object-valu — roottraveller, Dec 11 '20 at 16:18
Well I created an empty constructor as well, but no luck same issue, something wrong with the record — San Jaisy, Dec 11 '20 at 16:22

score 1 · Answer 1 · answered Dec 11 '20 at 16:31

I was missing @Introspected annotation in record

@Introspected
public record ProductViewModel
        (
                @JsonProperty("id")
                String id,

                @JsonProperty("name")
                String name,

                @JsonProperty("description")
                String description,

                @JsonProperty("price")
                Float price
        ) {
}

Failed to convert argument [model] for value [null] due to: Cannot construct instance of `view.model.product.ProductViewModel`

1 Answers1