JAX-RS-XML<-&燃气轮机；java.util.List

我试图访问一个JAX-RS Web服务，该服务返回一个XML格式的java.util.list值，但在客户端我得到了javax.XML.bind.UnmarshalException

Web服务方法：

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

MessdatenPCommon类：

@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 ...

}

有人能帮我吗

---

谢谢

我假设您希望收到

MessdatenPv

的实例，它是

MessdatenPCommon

的子类？这是因为

MessdatenPCommon

是抽象的，而

MessdatenPv

是

@xmlse注释中的参考。您需要确保XML包含必要的
xsi:type
属性来指示子类型

您可以封送数据以查看反汇编上的预期内容。
您的客户机代码看起来像是要将返回值反汇编到
MessdatenPCommon
-实体的列表中（
et（new GenericType（）{}）
。该类是抽象的，因此无法创建它的实例。请改用MessdatenPv的具体子类尝试调用。谢谢，这就是我问题的解决方案。
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)
....

@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 ...

}