title: XmlRootElement annotation at abstract class - possible?
body: <p>This is what I'm trying to do:</p>
  
  <pre><code>@XmlRootElement(name = "bar")
  @XmlAccessorType(XmlAccessType.NONE)
  public abstract class Bar {
  }
  
  public final class Foo extends Bar {
      @XmlElement
      public String getMsg() {
          return "hello, world!";
      }
  }
  </code></pre>
  
  <p>Now I'm trying to marshall an instance of class <code>Foo</code>:</p>
  
  <pre><code>com.sun.istack.SAXException2: unable to marshal type "Foo" as 
  an element because it is missing an @XmlRootElement annotation
  </code></pre>
  
  <p>What is a workaround?</p>