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What could be the reason of auto datetime conversion in java api response

I created one simple model class User. I used Util date here.
class User{
private int id;
private String name;
private Date createdAt;
}
On user post API call, I simply do setCreatedAt(new Date).
The problem is in the response, I am getting createdAt as -5.30 of the actual time. No additional time conversion method is called.
For Example, I hit the POST API user created at 28-10-2021 11:30:00 which I can see in the logs. But when it returns the response to the postman it shows 28-10-2021 06:00:00 time. There is no time conversion method in the code. I checked the return object in the return statement in debug mode even there is showing 28-10-2021 11:30:00.
I wanted to know where is this conversion happening. And how to stop this.
If it's the problem with datetime library, then which one should I use.
Extra information:
* My system timezone is in UTC.
* I am using ubuntu.
* Creating restFull APIs(JaxRs)
EDIT 1:
client and server are on the same machine(UTC timezone). For client, I am using Postman.
URL: [POST] /user
Request Body:
{
"name": "XYZ"
}
Actual Response:
{
"id": 1,
"name": "XYZ",
"createdAt: "28-10-2021 06:00:00"
}
Expected Response:
{
"id": 1,
"name": "XYZ",
"createdAt: "28-10-2021 11:30:00"
}

On user post API call, I simply do setCreatedAt(new Date).
It appears that you have not set the timezone while creating an instance of java.util.Date
By default it will set as UTC irrespective of your system timezone. You can use the https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html instead.
final TIMEZONE = ""; // need to set the timezone here
SimpleDateFormat formatter = new SimpleDateFormat("dd-M-yyyy hh:mm:ss", Locale.ENGLISH);
formatter.setTimeZone(TimeZone.getTimeZone(TIMEZONE));
String dateInString = "28-10-2021 11:30:00";
Date date = formatter.parse(dateInString);

There might be JsonFormat annotations that have timeZone issues. Please check the link for more details on the issue.jackson-data-bind issue Overriding the timezone in ObjectMapper didn't work either. You can refer the solved example by implementing a custom Date Deserializer as below:
#Component
public class CustomDateDeserializer extends StdDeserializer<Date> {
private static final long serialVersionUID = 1L;
private SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); // specify your specific timezone
public CustomDateDeserializer() {
this(null);
}
public CustomDateDeserializer(Class<?> vc) {
super(vc);
}
#Override
public Date deserialize(JsonParser jsonparser, DeserializationContext context)
throws IOException, JsonProcessingException {
String date = jsonparser.getText();
try {
return formatter.parse(date);
} catch (ParseException e) {
throw new RuntimeException(e);
}
}
}
Also, add the deserializer on the setter method in your bean properties.
#JsonDeserialize(using = CustomDateDeserializer.class)
public void setReturnDateTime(Date returnDateTime) {
this.returnDateTime = returnDateTime;
}

Date as #QueryParam in JAX-RS RestEasy [duplicate]

I have a service defined as follows.
public String getData(#QueryParam("date") Date date)
I'm trying to pass a java.util.Date to it from my client (which is jaxrs:client of CXF, not a generic HTTP client or browser).
My service receives the date as Thu Mar 01 22:33:10 IST 2012 in the HTTP URL. Since CXF won't be able to create a Date object using this String, my client receives a 404 error.
I tried using a ParameterHandler on the service side, but I still can't parse it successfully because I'm not expecting the date in any specific format.
As per this post, passing a Date is supposed to work out of the box, but I can't seem to get the basic case working. Am I required to do anything in order to successfully pass a Date object from my client to service? Appreciate any help.
Thanks

The problem is that JAX-RS dictates that parameter unbundling be done in one of two ways:
The parameter bean has a public constructor that accepts a String
The parameter bean has a static valueOf(String) method.
In your case, the Date is being unbundled via its Date(String) constructor, which cannot handle the input format your client is sending. You have a couple options available to remedy this:
Option 1
Get your client to change the format of the date before they send it. This is the ideal, but probably the hardest to accomplish!
Option 2
Handle the crazy date format. The options for this are:
Change your method signature to accept a string. Attempt to construct a Date object out of that and if that fails, use your own custom SimpleDateFormat class to parse it.
static final DateFormat CRAZY_FORMAT = new SimpleDateFormat("");
public String getData(#QueryParam("date") String dateString) {
final Date date;
try {
date = new Date(dateString); // yes, I know this is a deprecated method
} catch(Exception e) {
date = CRAZY_FORMAT.parse(dateString);
}
}
Define your own parameter class that does the logic mentioned above. Give it a string constructor or static valueOf(String) method that invokes the logic. And an additional method to get the Date when all is said and done.
public class DateParameter implements Serializable {
public static DateParameter valueOf(String dateString) {
try {
date = new Date(dateString); // yes, I know this is a deprecated method
} catch(Exception e) {
date = CRAZY_FORMAT.parse(dateString);
}
}
private Date date;
// Constructor, Getters, Setters
}
public String getData(#QueryParam("date") DateParameter dateParam) {
final Date date = dateParam.getDate();
}
Or finally, you can register a parameter handler for dates. Where its logic is simply the same as mentioned for the other options above. Note that you need to be using at least CXF 2.5.3 in order to have your parameter handler evaluated before it tries the default unbundling logic.
public class DateHandler implements ParameterHandler<Date> {
public Map fromString(String s) {
final Date date;
try {
date = new Date(dateString); // yes, I know this is a deprecated method
} catch(Exception e) {
date = CRAZY_FORMAT.parse(dateString);
}
}
}

Percepiton's answer was very useful, but ParameterHandler has been deprecated in Apache-cxf 3.0, see the Apache-cxf 3.0 Migration Guide:
CXF JAX-RS ParameterHandler has been dropped, please use JAX-RS 2.0 ParamConverterProvider.
So I add an example with the ParamConverterProvider :
public class DateParameterConverterProvider implements ParamConverterProvider {
#Override
public <T> ParamConverter<T> getConverter(Class<T> type, Type type1, Annotation[] antns) {
if (Date.class.equals(type)) {
#SuppressWarnings("unchecked")
ParamConverter<T> paramConverter = (ParamConverter<T>) new DateParameterConverter();
return paramConverter;
}
return null;
}
}
public class DateParameterConverter implements ParamConverter<Date> {
public static final String format = "yyyy-MM-dd"; // set the format to whatever you need
#Override
public Date fromString(String string) {
SimpleDateFormat simpleDateFormat = new SimpleDateFormat(format);
try {
return simpleDateFormat.parse(string);
} catch (ParseException ex) {
throw new WebApplicationException(ex);
}
}
#Override
public String toString(Date t) {
return new SimpleDateFormat(format).format(t);
}
}
The #SuppressWarnings is required to suppress an "unchecked or unsafe operations" warning during compilation. See How do I address unchecked cast warnings for more details.
The ParamConverterProvider can be registred as provider. Here is how I did it:
<jaxrs:server id="myService" address="/rest">
<jaxrs:serviceBeans>
...
</jaxrs:serviceBeans>
<jaxrs:providers>
<ref bean="dateParameterConverterProvider" />
</jaxrs:providers>
</jaxrs:server>
<bean id="dateParameterConverterProvider" class="myPackage.DateParameterConverterProvider"/>
See Apache-cxf JAX-RS : Services Configuration for more information.

Using a custom DateParam class seems the safest option. You can then base your method signatures on that and implement the ugly conversion logic inside the valueOf() method or the class constructor. It is also more self-documenting than using plain strings

As #Perception suggests in option two, you can handle the date. But you should use following:
private Date getDateFromString(String dateString) {
try {
DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
Date date = df.parse(dateString);
return date;
} catch (ParseException e) {
//WebApplicationException ...("Date format should be yyyy-MM-dd'T'HH:mm:ss", Status.BAD_REQUEST);
}
}
You call it from within the resource as
Date date = getDateFromString(dateString);//dateString is query param.

Jackson DateFormatter set timezone without changing time

I have a problem with jackson.
I have a date in the database in the following format :
2018-01-01 13:00:00
I convert the Database entry to a "Date" object.
I now want the jackson objectmapper to print it out date in the following format like :
2018-01-01T13:00:00.000+0200
Now I have the following code where I set up my objectmapper
private static ObjectMapper init() {
ObjectMapper mapper = new ObjectMapper();
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM dd'T'HH:mm:ss.SSSZ");
dateFormat.setTimeZone(TimeZone.getTimeZone("Europe/Berlin"));
mapper.setDateFormat(dateFormat);
mapper.registerModule(new JavaTimeModule());
mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
return mapper;
}
Now the problem is, that the date is printed out like this :
2018-01-01T15:00:00.000+0200
While formatting the date and adding the timezone information, it calculates the new time. All my dates use the "Europe/Berlin" timezone but I don't save it with this information in the database.
Is there any way how to add the timezone information without changing the time?
Regards

The solution was to use a custom DateFormat class, where I can handle the formatting.
Very important :
You have to implement the "clone" method. If you use Eclipse it only shows an error for the missing format and parse method. The clone method was missing and i got some nullpointer exceptions at the DateFormat class.
mapper.setDateFormat(JsonDateFormat);
public class JsonDateFormat extends DateFormat implements Serializable, Cloneable {
#Override
public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) {
// TODO DO STUFF
return toAppendTo;
}
#Override
public Date parse(String source, ParsePosition pos) {
// TODO DO STUFF
return null;
}
#Override
public Object clone() {
return new JsonDateFormat();
}
}

java jackson mapper convert unix timestamp to date, result wrong [duplicate]

I've got some JSON that has timestamps in seconds (i.e. a Unix timestamp):
{"foo":"bar","timestamp":1386280997}
Asking Jackson to deserialize this into an object with a DateTime field for the timestamp results in 1970-01-17T01:11:25.983Z, a time shortly after the epoch because Jackson is assuming it to be in milliseconds. Aside from ripping apart the JSON and adding some zeros, how might I get Jackson to understand the seconds timestamp?

I wrote a custom deserializer to handle timestamps in seconds (Groovy syntax).
class UnixTimestampDeserializer extends JsonDeserializer<DateTime> {
Logger logger = LoggerFactory.getLogger(UnixTimestampDeserializer.class)
#Override
DateTime deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException {
String timestamp = jp.getText().trim()
try {
return new DateTime(Long.valueOf(timestamp + '000'))
} catch (NumberFormatException e) {
logger.warn('Unable to deserialize timestamp: ' + timestamp, e)
return null
}
}
}
And then I annotated my POGO to use that for the timestamp:
class TimestampThing {
#JsonDeserialize(using = UnixTimestampDeserializer.class)
DateTime timestamp
#JsonCreator
public TimestampThing(#JsonProperty('timestamp') DateTime timestamp) {
this.timestamp = timestamp
}
}

#JsonFormat(shape=JsonFormat.Shape.STRING, pattern="s")
public Date timestamp;
edit: vivek-kothari suggestion
#JsonFormat(shape=JsonFormat.Shape.NUMBER, pattern="s")
public Timestamp timestamp;

A very similar approach to that of #DrewStephens's which uses the Java SE TimeUnit API (introduced in JDK1.5) instead of plain String concatenation and is thus (arguably) a little bit cleaner and more expressive:
public class UnixTimestampDeserializer extends JsonDeserializer<Date> {
#Override
public Date deserialize(JsonParser parser, DeserializationContext context)
throws IOException, JsonProcessingException {
String unixTimestamp = parser.getText().trim();
return new Date(TimeUnit.SECONDS.toMillis(Long.valueOf(unixTimestamp)));
}
}
Specifying your custom deserializer (UnixTimestampDeserializer) on the affected Date field(s):
#JsonDeserialize(using = UnixTimestampDeserializer.class)
private Date updatedAt;

I had this exact issue, except my ZonedDateTime objects got turned to unix-timestamps (seconds) and I needed them in milliseconds (to initialize JS Date objects on the browser).
Implementing a custom serializer/deserializer looked like too much work for something that should be pretty straightforward, so I looked elsewhere and found that I can just configure the object mapper for the desired result.
Because my application already overrides the default ObjectMapper provided by Jersey, I just had to disable SerializationFeature.WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS.
Here's my code
#Provider
public class RPObjectMapperProvider implements ContextResolver<ObjectMapper> {
final ObjectMapper defaultObjectMapper;
public RPObjectMapperProvider() {
defaultObjectMapper = new ObjectMapper();
// this turned ZonedDateTime objects to proper seconds timestamps
defaultObjectMapper.enable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
// disable to serialize dates for millis timestamps
defaultObjectMapper.disable(SerializationFeature.WRITE_DATE_TIMESTAMPS_AS_NANOSECONDS);
// using Java8 date time classes
defaultObjectMapper.registerModule(new JavaTimeModule());
}
#Override
public ObjectMapper getContext(Class<?> type) {
return defaultObjectMapper;
}
}
And that's it

Mapping Java Date Object to XML Schema datetime format

I am having some problem mapping my Java Data Type to standard Schema Date data type.
I have a simple class that I annotated like this. The period instance variable is of Java Date object type.
#XmlAccessorType(value = XmlAccessType.NONE)
public class Chart {
#XmlElement
private double amount;
#XmlElement
private double amountDue;
#XmlElement
private Date period;
//constructor getters and setters
}
Here is my Web Service
#WebService
public class ChartFacade {
#WebMethod
public Chart getChart() throws ParseException {
SimpleDateFormat df = new SimpleDateFormat("yyyy-mm-dd");
Chart chart = new Chart(20.0,20.5, df.parse("2001-01-01"));
return chart;
}
}
My problem is it returns the date data in a format not according to what I am expecting.
<S:Envelope xmlns:S="http://schemas.xmlsoap.org/soap/envelope/">
<S:Body>
<ns2:getChartResponse xmlns:ns2="http://ss.ugbu.oracle.com/">
<return>
<amount>20.0</amount>
<amountDue>20.5</amountDue>
**<period>2001-01-01T00:01:00+08:00</period>**
</return>
</ns2:getChartResponse>
</S:Body>
</S:Envelope>
I wanted the period element to be returned like this
<period>2001-01-01</period>
Is there any way I can achieve this?

You can do the following to control the schema type:
#XmlElement
#XmlSchemaType(name="date")
private Date period;
For More Information:
http://bdoughan.blogspot.com/2011/01/jaxb-and-datetime-properties.html

Use #XmlJavaTypeAdapter annotation and you can marshal/unmarshal your fields any way you want.
Cannot tell though if it's the simplest way.
And note also that it may harm interoperability with any code that would try to use your WSDL. The programmers for that other code would see xsd:string as the field type, and therefore will have to do formatting and parsing manually (just like you do, yes), introducing who knows how many bugs. So please consider if the xsd:date a bad choice really.
Stolen from here:
#XmlJavaTypeAdapter(value=DateAdapter.class, type=Date.class)
Date someDate;
...
public class DateAdapter extends XmlAdapter<String, Date> {
// the desired format
private String pattern = "MM/dd/yyyy";
public String marshal(Date date) throws Exception {
return new SimpleDateFormat(pattern).format(date);
}
public Date unmarshal(String dateString) throws Exception {
return new SimpleDateFormat(pattern).parse(dateString);
}
}
UPDATE: as was mentioned by #Blaise Doughan, a much shorter way is to annotate the date with
#XmlSchemaType("date")
Date someDate;
Despite it is still not clear why timezone information is not generated for the date, this code works in practice and requires much less typing.

Your Chart constructor seems to be parsing the formatted date string back into a Date, which is then being serialized using the default format to the XML response.
I guess using private String period; (and fixing the constructors) should work