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Null OptionalInt deseralized as null [message #1750493]

Wed, 21 December 2016 16:42

Jean-Francois James

Messages: 5
Registered: December 2016

Junior Member

I've done a small test with a Person class having an OptionalInt attribute (see attached file).
Serialisation and deserialization are OK with a non empty value.
Seralization is OK with an empty value. But deserialization is not: the field value is null instead of being an empty OptionalInt.
This seems in contradiction with the specification (chapter 3.14.1 related to Null Java field). Is it a bug or do I miss something?

Attachment: OptionalIntTest.java
(Size: 3.79KB, Downloaded 165 times)

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Re: Null OptionalInt deseralized as null [message #1750549 is a reply to message #1750493]

Thu, 22 December 2016 13:36

Ehsan Zaery Moghaddam

Messages: 8
Registered: December 2016

Junior Member

Hi Jean-Francois

The second paragraph of chapter 3.14.1 is:

Quote:

The deserialization operation of a property absent in JSON document MUST not set the value of the field, the setter (if available) MUST not be called, and thus original value of the field MUST be preserved.

In your second test, the OptionalInt property doesn't exist on the JSON string, so it's value remains untouched during deserialization process.

Regards
Ehsan

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Re: Null OptionalInt deseralized as null [message #1750601 is a reply to message #1750549]

Fri, 23 December 2016 08:21

Jean-Francois James

Messages: 5
Registered: December 2016

Junior Member

Hi Ehsan

Thank you for your relevant answer. It helps me understand the subtelities of the spec.
To force the serialization of the OptionalInt attribute with a null value, I've added a @JsonbProperty(nullable=true) on it.
This time we can see that serialization is compliant with the specification: jsonData={"age":null,"name":"Jack"}.

However, deserialization of the same data leads to a null value instead of an OptionalInt.empty: Person{name=Jack, age=null}.
This seems in contradiction with specification:
Quote:

The deserialization operation of a property with a null value in a JSON document MUST set the value of the field to null value (or call setter with null value if setter is present). The exception is java.util.Optional, OptionalInt OptionalLong, OptionalDouble instances. In this case the value of the field is set to an empty optional value.

Please find attached my changed ready-to-run example.