Returning data when using Spring 3, ReST, and XML with Joda date types

I am having开发者_开发百科 an odd problem in a simple web service built with Spring 3 and MVC. The web service works ok and I get XML back just like I want, however, all the values for all Joda date/time types are empty.

So I have a UserDTO which is something like this:

@XmlRootElement(name = "user")
public class UserDTO
{
  private String firstname;
  private String lastname;
  private LocalDate birthdate;
  ...

And I have a controller like:

@Controller
public class UserController
{
    @RequestMapping(value = "/user", method = RequestMethod.GET)
    @ResponseBody
    public UserDTO getUser()
    {
        UserDTO userDTO = new UserDTO();
        userDTO.setFirstname("Foo");
        userDTO.setLastname("Bar");
        userDTO.setBirthdate(new LocalDate(1980,1,1));
        return userDTO;
    }
}

I get the following XML back:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<user>
  <firstname>Foo</firstname>
  <lastname>Bar</lastname>
  <birthdate />
</user>

If I change the 'Accept' header to application/json, I do get the date value

{"userVO":{"First Name","lastname":"Last Name","birthdate":[1978,12,5]}}

Any ideas on what this could be?

---

To answer my own question... the following link set me on the right path: http://bdoughan.blogspot.com/2011/05/jaxb-and-joda-time-dates-and-times.html

Basically you have to create an XmlAdapter for each type. Here is an example from the link:

package blog.jodatime;

import javax.xml.bind.annotation.adapters.XmlAdapter;
import org.joda.time.DateTime;

public class DateTimeAdapter 
    extends XmlAdapter<String, DateTime>{

    public DateTime unmarshal(String v) throws Exception {
        return new DateTime(v);
    }

    public String marshal(DateTime v) throws Exception {
        return v.toString();
    }

}