No Object Id found for an instance of 'class', to assign to property '@id'

[Asayu233]

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Describe the bug

When running the following code, it throws MismatchedInputException. I don't know what happened.

Version Information

2.18.3

Reproduction

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonIdentityInfo;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.ObjectIdGenerators;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;

import java.util.List;
import java.util.Map;

@JsonIdentityInfo(generator = ObjectIdGenerators.UUIDGenerator.class)
class Ability {
    private final String name;
    private final Map<String, List<Modifier>> modifiers;

    @JsonCreator
    public Ability(@JsonProperty("name") String name,
                   @JsonProperty("modifiers") Map<String, List<Modifier>> modifiers) {
        this.name = name;
        this.modifiers = modifiers;
    }

    public String getName() {
        return name;
    }

    public Map<String, List<Modifier>> getModifiers() {
        return modifiers;
    }
}

class Modifier {
    private final String name;
    private final Ability parent;

    @JsonCreator
    public Modifier(@JsonProperty("name") String name,
                    @JsonProperty("parent") Ability parent) {
        this.name = name;
        this.parent = parent;
    }

    public String getName() {
        return name;
    }

    public Ability getParent() {
        return parent;
    }
}

public class Main {
    public static void main(String[] args) {
        String yaml = """
            &12345678-aaaa-bbbb-cccc-87654321abcd
            name: TestAbility
            modifiers:
              TestModifier:
              - name: TestModifier
                parent: *12345678-aaaa-bbbb-cccc-87654321abcd
            """;

        ObjectMapper mapper = new ObjectMapper(new YAMLFactory());
        try {
            mapper.readValue(yaml, Ability.class);
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

Expected behavior

No response

Additional context

No response

[cowtowncoder]

YAML-specific, will need to move to proper repo

[cowtowncoder]

Quick note: I don't know where YAML String is gotten from so whether it is valid representation of given classes is unclear. Jackson supports "reading what it writes", so the real test would be that YAML generated can be read back: that is, test would create instance of Ability, write it out as YAML, then try read back.

Doing this might also suggest what is different with YAML content included here.