Jackson Databind error when reading in a POST method

Question

I am trying to create a POST endpoint which receives a ClassB. This class is a subtype of an abstract class ClassA, and there is another ClassC which is a subclass from ClassA. This is like that, because ClassB has a collection of ClassA, so ClassB can contain multiple ClassB or ClassC.

The problem is that I always get a Jackson Databind error while processing the request:

An unknown error occurred while processing the request.: com.fasterxml.jackson.databind.exc.InvalidTypeIdException: Could not resolve subtype of [simple type, class ClassB]: missing type id property 'type'
at [Source: (io.undertow.servlet.spec.ServletInputStreamImpl); line: 67, column: 1]
    at com.fasterxml.jackson.databind.exc.InvalidTypeIdException.from(InvalidTypeIdException.java:43)
    at com.fasterxml.jackson.databind.DeserializationContext.missingTypeIdException(DeserializationContext.java:2083)
    at com.fasterxml.jackson.databind.DeserializationContext.handleMissingTypeId(DeserializationContext.java:1596)
    at com.fasterxml.jackson.databind.jsontype.impl.TypeDeserializerBase._handleMissingTypeId(TypeDeserializerBase.java:307)
    at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer._deserializeTypedUsingDefaultImpl(AsPropertyTypeDeserializer.java:185)
    at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer.deserializeTypedFromObject(AsPropertyTypeDeserializer.java:119)
    at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeWithType(BeanDeserializerBase.java:1292)

I have the abstract ClassA as follows:

@JsonTypeInfo(
        use = JsonTypeInfo.Id.NAME,
        include = JsonTypeInfo.As.PROPERTY,
        property = "type")
@JsonSubTypes({
        @JsonSubTypes.Type(value = ClassB.class, name = "classb"),
        @JsonSubTypes.Type(value = ClassC.class, name = "classc")})
public abstract class ClassA {

    public ClassA () {
    }
}

The ClassB:

@Builder
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@JsonTypeName("classb")
public class ClassB extends ClassA implements Serializable {
  ...
  private Collection<ClassA> myList;
  ...
}

And the ClassC is created like ClassB, but with the "classc" jsonTypeName and without the collection of ClassA elements.

In the pom.xml I have the following dependency:

<dependency>
  <groupId>io.quarkus</groupId>
  <artifactId>quarkus-resteasy-jackson</artifactId>
</dependency>

Previously I also had the jsonb dependency in the pom.xml:

<dependency>
  <groupId>io.quarkus</groupId>
  <artifactId>quarkus-resteasy-jsonb</artifactId>
</dependency> 

But I commented it out because I thought it could cause some conflict.

In the API, I have the following method:

@POST
@Consumes(MediaType.APPLICATION_JSON)
public Response createClassB(ClassB classB, @Context UriInfo uriInfo) {
    ...
}

But I always get the same error, as if I would not have added the @JsonTypeName annotation in ClassB and ClassC.

Is there something I am missing?

---

EDIT: This is the request that I am sending:

{
  ...
  "myList" : [ {
    "type" : "classb",
    ...
  }, {
    "type" : "classb",
    ...
  } ],
  "user" : null
}

Answer 1

try adding type property on the root object...

{
  ...
  "type" : "classb",
  "myList" : [ {
    "type" : "classb",
    ...
  }, {
    "type" : "classb",
    ...
  } ],
  "user" : null
}