[JOHNZON-402] Polymorphism attributes not serialized if @JsonbTypeInfo is not attached to direct parent

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 2.0.1
• Component/s: JSON-B
• Assignee: Markus Jung
• Reporter: Markus Jung
• Created: 28/Jan/24 16:01
• Updated: 01/Apr/24 18:38
• Resolved: 10/Feb/24 13:27

Description

After thinking through the polymorphism code again for JONZON-401 I noticed an issue where polymorphism properties aren't taken into account if the @JsonbTypeInfo annotation is not attached to a direct parent of the serialized class.

Take this example test:

public class JsonbMultiLevelPolymorphismTest {
    @Rule
    public JsonbRule jsonb = new JsonbRule();

    @Test
    public void test() {
        ConcreteSomething info = new ConcreteSomething();

        assertEquals("{\"@type\":\"concrete\"}", jsonb.toJson(info));
    }

    @JsonbTypeInfo(
            @JsonbSubtype(alias = "concrete", type = ConcreteSomething.class)
    )
    public static abstract class AbstractTopLevelSomething { }
    public static abstract class AbstractMiddleLevelSomething extends AbstractTopLevelSomething { }
    public static class ConcreteSomething extends AbstractMiddleLevelSomething { }
} 

Test result:

org.junit.ComparisonFailure: 
Expected :{"@type":"concrete"}
Actual   :{} 

 

The spec doesn't mention that @JsonbTypeInfo has to be attached to a direct parent. This also works perfectly fine in yasson, so I see no reason why it should not in johnzon.