Serialize Date in a JSON REST web service as ISO-8601 string

Question

I have a JAX-RS application using JBoss AS 7.1, and I POST/GET JSON and XML objects which include Dates (java.util.Date):

@XmlRootElement
@XmlAccessorType(XmlAccessField.FIELD)
public class MyObject implements Serializable
{
    @XmlSchemaType(name = "dateTime")
    private Date date;
    ...
}

When I use @Produce("application/xml") on the get method, the objets are serialized as XML and the dates are converted into ISO-8601 strings (e.g. "2012-12-10T14:50:12.123+02:00").

However, if I use @Produce("application/json") on the get method, the dates in the JSON objects are timestamps (e.g. "1355147452530") instead of ISO-8601 strings.

How can I do to configure the JAX-RS implementation (RESTEasy) to serialize dates in JSON format as ISO-8601 strings instead of timestamps ?

Thank you for your answers.

Note: I also tried to use a custom JAX-RS provider to do the JSON serialization for Dates

@Provider
@Produces(MediaType.APPLICATION_JSON)
public class CustomJsonDateProvider implements MessageBodyWriter<Date>
{
    ...
}

This provider seems to be registered by RESTeasy on JBoss startup:

[org.jboss.jaxrs] Adding JAX-RS provider classes: package.CustomJsonDateProvider
...
[org.jboss.resteasy.cdi.CdiInjectorFactory] No CDI beans found for class package.CustomJsonDateProvider. Using default ConstructorInjector.

but it is never used !

Answer 1

I assume your json parser is Jackson, try:

@JsonFormat(shape=JsonFormat.Shape.STRING, pattern="yyyy-MM-dd,HH:00", timezone="CET")
public Date date;

(since Jackson 2.0)