title: Java Web Services/JAXB - Abstract superclass
body: <p>I have a package with JAXB annotated classes with an abstract superclass. I want to use this superclass in web service interface, so I
  can pass any of subclasses as a parameter. When I do it, an exception is thrown:</p>
  
  <pre><code>javax.xml.ws.WebServiceException: javax.xml.bind.UnmarshalException
  - with linked exception:
  [javax.xml.bind.UnmarshalException: Unable to create an instance of xxx.yyy.ZZZ
  - with linked exception:
  [java.lang.InstantiationException]]
  </code></pre>
  
  <p>It is possible to manually marshall/unmarshall &amp; pass parameter as a string, but I would like to avoid it. Any ideas how to do it?</p>