Serialization and deserialization issue of sub-types used with JsonTypeInfo.Id.DEDUCTION where sub-types are Object and Array #4772
Description
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- I searched in the issues and found nothing similar.
Describe the bug
Having the following class structure and annotations the deserialization and serialization doesn't work (but expected):
@JsonTypeInfo(use = JsonTypeInfo.Id.DEDUCTION)
@JsonSubTypes({@JsonSubTypes.Type(DataObject.class), @JsonSubTypes.Type(DataArray.class)})
interface Data {
}
static class DataItem {
String id;
}
static class DataObject extends DataItem implements Data {
@JsonCreator
DataObject(@JsonProperty("id") String id) {
super(id);
}
}
static class DataArray extends ArrayList<DataItem> implements Data {
@JsonCreator
DataArray(Collection<DataItem> items) {
super(new ArrayList<>(items));
}
}
static class Container {
Data data;
}
Version Information
2.18.0
and, I believe, 2.19
Reproduction
Here is a test case that I made passing: https://github.com/Gems/jackson-databind/blob/contrib/2.18-1/src/test/java/com/fasterxml/jackson/databind/jsontype/TestPolymorphicDeductionObjectVsArray.java
To make Deserialization work, I had to change @JsonTypeInfo annotation to @JsonTypeInfo(use = JsonTypeInfo.Id.DEDUCTION, defaultImpl = DataArray.class)
To make Serialization work, I had to fix JsonGenerator::writeTypePrefix method (comes from jackson-core) to ignore making WRAPPER_ARRAY in case typeIdDef.id == null.
Expected behavior
I'd expect that with the mentioned definition the deserialization and serialization goes smooth without tweaks that I made, but not sure if this expectation is aligned with the vision for the library design.
Thanks in advance for consideration and comments.
Additional context
No response