I'm using Jackson 2.8 and need to communicate with an API that doesn't allow milliseconds within ISO 8601 timestamps.
The expected format is this: "2016-12-24T00:00:00Z"
I'm using Jackson's JavaTimeModule with WRITE_DATES_AS_TIMESTAMPS
set to false
.
But this will print milliseconds.
So I tried to use objectMapper.setDateFormat
which didn't change anything.
My current workaround is this:
ObjectMapper om = new ObjectMapper();
DateTimeFormatter dtf = new DateTimeFormatterBuilder()
.appendInstant(0)
.toFormatter();
JavaTimeModule jtm = new JavaTimeModule();
jtm.addSerializer(Instant.class, new JsonSerializer<Instant>() {
@Override
public void serialize(Instant value, JsonGenerator gen, SerializerProvider serializers) throws IOException, JsonProcessingException {
gen.writeString(dtf.format(value));
}
});
om.registerModule(jtm);
I'm overriding the default serializer for Instant.class
which works.
Is there any nice way using some configuration parameter to solve this?
Just add a @JsonFormat
annotation whith the date format above the Instant
property. It's very easy.
In the case you have an ObjectMapper with the JavaTimeModule
like next:
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JavaTimeModule());
If you have a class with an Instant
property, you should add the @JsonFormat
annotation and put the date pattern which hasn't milliseconds. It would be like next:
public static class TestDate {
@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd hh:mm:ss", timezone = "UTC")
Instant instant;
//getters & setters
}
So if you serialize an object to Json it works perfectly:
String json = mapper.writeValueAsString(testDate);
System.out.println(json);
Output
{"instant":"2016-11-10 06:03:06"}
You could use the Jackson2ObjectMapperBuilder
to build it.
You just need to add the dateFormat you want. It would be something like next:
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
ObjectMapper mapper = Jackson2ObjectMapperBuilder
.json()
.featuresToDisable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
.modules(new JavaTimeModule())
.dateFormat(dateFormat)
.build();