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@JsonFormat (and other annotations) is ignored after adding custom serializer to specified type
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Describe the bug
Problem:
I wanted to change default pattern of formatting for OffsetDateTime (only if the field is not annotated with @JsonFormat)
Solution:
I realized custom serializer which extends JsonSerializer<OffsetDateTime>. I also implemented ContextualSerializer in order to define is field annotated or not, all annotated fields will be passed to default serializer. I made custom modifier (exteded BeanSerializerModifier) to get and pass default serializer to my custom serializer.
I tested my serializer with unannotated OffsetDateTime fields and default format is working. But when I tried fields with @JsonFormat(pattern=...), I realized that defaultSerializer has ignored the pattern and used its default one but I expected pattern which is defined in @JsonFormat
Version Information
2.15.4
Reproduction
Custom Serializer:
class CustomOffsetDateTimeSerializer(
private val defaultSerializer: JsonSerializer<*>,
private val formatter: DateTimeFormatter = DateTimeFormatter.ofPattern(defaultPattern),
) : JsonSerializer<OffsetDateTime>(), ContextualSerializer {
companion object {
private const val defaultPattern = "yyyy-MM-dd'T'HH:mm"
}
override fun serialize(
value: OffsetDateTime,
jsonGenerator: JsonGenerator,
serializerProvider: SerializerProvider?,
) {
jsonGenerator.writeString(formatter.format(value))
}
override fun createContextual(
prov: SerializerProvider?,
property: BeanProperty?,
): JsonSerializer<*> {
if (property?.getAnnotation(JsonFormat::class.java) != null) {
return defaultSerializer
}
return CustomOffsetDateTimeSerializer(defaultSerializer)
}
}
Custom Modifier:
class CustomOffsetDateTimeModifier : BeanSerializerModifier() {
override fun modifySerializer(
config: SerializationConfig?,
beanDesc: BeanDescription,
serializer: JsonSerializer<*>,
): JsonSerializer<*> {
if (beanDesc.beanClass == OffsetDateTime::class.java) {
return CustomOffsetDateTimeSerializer(serializer)
}
return super.modifySerializer(config, beanDesc, serializer)
}
}
Expected behavior
No response
Additional context
No response
2.15.4 is not the latest so please make sure to verify with 2.17.2 or 2.18.0-rc1. Ideally before filing issue :)
Also looks like reproduction is in Kotlin so I may need to move to Kotlin module (although might be easy enough to translate to plain Java to keep here).
Also: code is not complete enough as reproduction: would need code to show configuration, calls to serialize.
