ObjectMapper#setTimeZone ignored by jsr-310/datetime types during serialization when using `@JsonFormat` annotation

[ErwanLeroux]

Hello, i have an issue regarding the serialization of OffsetDateTime, the timezone i set in the object mapper is not used

With the following code

public class POJO {
    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss.SSSXXX")
    private OffsetDateTime offsetDateTimeWithoutTimeZone;
}

public static void setUp() {
    mapperWithTimezone = new ObjectMapper()
            .registerModule(new JavaTimeModule())
            .disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
            .setTimeZone(TimeZone.getTimeZone("Europe/Paris"))
            .enable(SerializationFeature.INDENT_OUTPUT);
}

final OffsetDateTime firstJune2020AtNoonOffsetUTC = OffsetDateTime.of(
        LocalDate.of(2020, Month.JUNE, 1),
        LocalTime.NOON,
        ZoneOffset.UTC);

final POJO pojoOffsetUTC = new POJO();
pojoOffsetUTC.setOffsetDateTimeWithoutTimeZone(firstJune2020AtNoonOffsetUTC);
final String strPojoOffSetUTC = mapperWithTimezone.writeValueAsString(pojoOffsetUTC);

I'm expecting that the output is

{"offsetDateTimeWithoutTimeZone" : "2020-06-01T14:00:00.000+02:00"}

but i get

{"offsetDateTimeWithoutTimeZone" : "2020-06-01T12:00:00.000Z"}

The javadoc of com.fasterxml.jackson.annotation.JsonFormat#timezone tells me that the default is the one specified in the objectMapper, but UTC is used instead.

I search a bit in the code, and i didn't see anything regarding the use of ObjectMapper#setTimezone in the method com.fasterxml.jackson.datatype.jsr310.ser.JSR310FormattedSerializerBase#createContextual

When i specify the timezone in the JsonFormat annotation, it work as intended, but i would prefer to have a global setting rather specifying it for each field.

I created a repo with a working code to illustrate my question : https://github.com/ErwanLeroux/jackson-issue

[cowtowncoder]

Sounds like a bug, thank you for reporting this.
I assume behavior is reproducible with 2.11.0?

[ErwanLeroux]

yes, i used the last version : implementation group: 'com.fasterxml.jackson.datatype', name: 'jackson-datatype-jsr310', version: '2.11.0'

[cowtowncoder]

Looking at Joda (jackson-datatype-joda) serializer implementation, it seems to use default timezone unless overridden by format annotation (or config override to same effect), see f.ex DateTimeSerializer (via JacksonJodaDateFormat).

But this is missing from jsr-310/datetime module, so it would need to be added.
I can help with this but probably will not have time in near future to tackle it myself.
Note, too, that it is not enough to handle this in createContextual() as that is not called on per-writeValue basis -- context timezone needs to be applied on per-call basis.

@kupci Not sure if this is something you are aware of.

[kupci]

But this is missing from jsr-310/datetime module, so it would need to be added.
Thanks for the details and ideas to fix, and thanks to Erwan for reporting and the test case. I'll edit the title to reflect the fact this impacts other types besides the OffsetDateTime type.