Java Jackson Polymorphic Deserialization

Main.java

package org.example;

import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonSubTypes;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.annotation.JsonTypeName;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.Builder;
import lombok.SneakyThrows;
import lombok.Value;
import lombok.extern.jackson.Jacksonized;
import lombok.val;

public class Main {
    @SneakyThrows
    public static void main(String[] args) {
        val fooJson = new ObjectMapper()
            .writeValueAsString(Foo.builder().field("foo").build());
        val barJson = new ObjectMapper()
            .writeValueAsString(Bar.builder().flag(123).build());
        val foo = new ObjectMapper()
            .readValue(fooJson, Trait.class);
        val bar = new ObjectMapper()
            .readValue(barJson, Trait.class);
        
        // class org.example.Foo
        // Foo(field=foo)
        // class org.example.Bar
        // Bar(flag=123)
        System.out.println(foo.getClass());
        System.out.println(foo);
        System.out.println(bar.getClass());
        System.out.println(bar);
    }
}

@JsonTypeInfo(
    use = JsonTypeInfo.Id.NAME,
    include = JsonTypeInfo.As.EXTERNAL_PROPERTY,
    property = "type")
@JsonSubTypes({
    @JsonSubTypes.Type(value = Foo.class, name = "Foo"),
    @JsonSubTypes.Type(value = Bar.class, name = "Bar")
})
interface Trait {
    @JsonIgnore
    String getMessage();
}


@Value
@Builder
@Jacksonized
@JsonTypeName("Foo")
class Foo implements Trait {
    String field;

    @Override
    public String getMessage() {
        return this.field;
    }
}

@Value
@Builder
@Jacksonized
@JsonTypeName("Bar")
class Bar implements Trait {
    int flag;

    @Override
    public String getMessage() {
        return String.valueOf(this.flag);
    }
}