title: JAXB unmarshal returning null values for attributes
body: <p>Can you please diagnose why my code prints out [null, null, null, null]:</p>
  
  <pre><code>Unmarshaller m = JAXBContext.newInstance(Roles.class).createUnmarshaller();
  Roles root = m.ummarshal(new FileReader("test.xml"));
  System.out.println(root);
  </code></pre>
  
  <p>I tried debugging in eclipse but breakpoints at the setters and getters don't hit</p>
  
  <p><strong>test.xml</strong></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8" ?&gt;
  &lt;Roles&gt;
   &lt;Ele Id="1" Value="Yes"/&gt;
   &lt;Ele Id="2" Value="Yes"/&gt;
   &lt;Ele Id="3" Value="No"/&gt;
   &lt;Ele Id="4" Value="Yes"/&gt;
  &lt;/Roles&gt;
  </code></pre>
  
  <p><strong>Roles.java</strong></p>
  
  <pre><code>@XmlRootElement(name="Roles")
  public class Roles {
   private List&lt;Ele&gt; EleList;
   public Roles() {super();}
  
   @XmlElement(name="Ele")
   public List&lt;Ele&gt; getEleList() {return EleList;}
   public void setEleList(List&lt;Ele&gt; EleList) {this.EleList = EleList;}
   public String toString() {return EleList.toString();}
  }
  </code></pre>
  
  <p><strong>Ele.java</strong></p>
  
  <pre><code>public class Ele {
  
   @XmlAttribute
   private String Id;
  
   @XmlAttribute
   private String Value;
  
   public Ele(){super();}
  
   public String getId() {return Id;}
   public void setId(String id) {Id = id;}
   public String getValue() {return Value;}
   public void setValue(String value) {Value = value;}
  
   public String toString() { if(Id == null || Value == null) return null; else return Id + Value;}
  }
  </code></pre>