Marshalling polymorphic objects in JAX-WS
- by pkchukiss
I'm creating a JAX-WS type webservice, with operations that return an object WebServiceReply. The class WebServiceReply itself contains a field of type Object. The individual operations would populate that field with a few different data-types, depending on the operation.
Publishing the WSDL (I'm using Netbeans 6.7), and getting a ASP.NET application to retrieve and parse the WSDL was fine, but when I tried to call an operation, I would receive the following exception:
javax.xml.ws.WebServiceException: javax.xml.bind.MarshalException
- with linked exception:
[javax.xml.bind.JAXBException: class [LDataObject.Patient; nor any of its super class is known to this context.]
How do I mark the annotations in the DataObject.Patient class, as well as the WebServiceReply class to get it to work? I haven't been able to fine a definitive resource on marshalling based upon annotations within the target classes either, so it would be great if anybody could point me to that too.
WebServiceReply.java
@XmlRootElement(name="WebServiceReply")
public class WebServiceReply {
private Object returnedObject;
private String returnedType;
private String message;
private String errorMessage;
.......... // Getters and setters follow
}
DataObject.Patient.java
@XmlRootElement(name="Patient")
public class Patient {
private int uid;
private Date versionDateTime;
private String name;
private String identityNumber;
private List<Address> addressList;
private List<ContactNumber> contactNumberList;
private List<Appointment> appointmentList;
private List<Case> caseList;
}
Solution
(Thanks to Gregory Mostizky for his answer)
I edited the WebServiceReply class so that all the possible return objects extend from a new class ReturnValueBase, and added the annotations using @XmlSeeAlso to ReturnValueBase. JAXB worked properly after that!
Nonetheless, I'm still learning about JAXB marshalling in JAX-WS, so it would be great if anyone can still post any tutorial on this.
Gregory: you might want to add-on to your answer that the return objects need to sub-class from ReturnValueBase. Thanks a lot for your help! I had been going bonkers over this problem for so long!
