JAX-RS球衣XML <-> java.util.List

Question

I try to access a JAX-RS Web Service which is returning me a java.util.list of Values in XML but I get javax.xml.bind.UnmarshalException in Client-Side...

Web Service method:

@GET
@Path("/getMessdaten")
@Produces(MediaType.APPLICATION_XML)
public List<MessdatenPCommon> getMessdatenValues() throws Exception {
    List<MessdatenPCommon> messdatenPList = testBean();
    return MessdatenPCommonList;}

access code in client:

List<MessdatenPCommon> m = webResource.path("test").path("helloworld/getMessdaten").accept(MediaType.APPLICATION_XML).et(new GenericType<List<MessdatenPCommon>>() {});

The Exception in Client:

Exception in thread "main" javax.ws.rs.WebApplicationException: javax.xml.bind.UnmarshalException
 - with linked exception:
[com.sun.istack.internal.SAXParseException2; lineNumber: 1; columnNumber: 89; Unable to create an instance of xx.xxxx.xxx.xxx.xxxxx.xxxx.MessdatenPCommon]
    at com.sun.jersey.core.provider.jaxb.AbstractListElementProvider.readFrom(AbstractListElementProvider.java:251)
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:553)
    at com.sun.jersey.api.client.ClientResponse.getEntity(ClientResponse.java:523)
    at com.sun.jersey.api.client.WebResource.handle(WebResource.java:686)
    at com.sun.jersey.api.client.WebResource.access$300(WebResource.java:74)
    at com.sun.jersey.api.client.WebResource$Builder.get(WebResource.java:508)
    at appclient.TestClient.main(TestClient.java:31)
Caused by: javax.xml.bind.UnmarshalException
 - with linked exception:
[com.sun.istack.internal.SAXParseException2; lineNumber: 1; columnNumber: 89; Unable to create an instance of xx.xxxxx.xxx.xxx.xxxxx.xxxxx.MessdatenPCommon]
    at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.handleStreamException(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(Unknown Source)
    at com.sun.jersey.core.provider.jaxb.AbstractListElementProvider.readFrom(AbstractListElementProvider.java:234)
    ... 6 more
Caused by: com.sun.istack.internal.SAXParseException2; lineNumber: 1; columnNumber: 89; Unable to create an instance of xx.xxxx.xxx.xxx.xxxx.xxxx.MessdatenPCommon
    at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallingContext.handleEvent(Unknown Source)
....

The MessdatenPCommon class:

@XmlSeeAlso({ MessdatenPv.class })
@XmlType
public abstract class MessdatenPCommon extends xx.xxxx.xxx.xxx.AbstractEntityBase {
    private static final long serialVersionUID = 1L;

    public abstract BigDecimal getNum();

    public abstract ...

}

Can anyone help me out?

Thx!

Answer 1

I am assuming you are expecting to receive an instance of MessdatenPv which is a subclass of MessdatenPCommon ? This is since MessdatenPCommon is abstract, and MessdatenPv is reference in the @XmlSeeAlso annotation. You will need to ensure that the XML contains the necessary xsi:type attribute to indicate the subtype.

You can marshal out the data to see what is expected on the unmarshal.