title: JAXB Unmarshalling an subset of Unknown XML content
body: <p>I have a requirement to <code>unmarshall</code> a subset of Unknown <code>XML</code> content, with that unmarshalled object, I need modify some contents and re-bind the same XML content(subset) with the Original  XML.</p>
  
  <p><strong>Sample Input XML:</strong></p>
  
  <pre><code>&lt;Message&gt;
      &lt;x&gt;
      &lt;/x&gt;
      &lt;y&gt;
      &lt;/y&gt;
      &lt;z&gt;
      &lt;/z&gt;
      &lt;!-- Need to unmarshall this content to "Content" - java Object --&gt;
      &lt;Content&gt;
          &lt;Name&gt;Robin&lt;/Name&gt;
          &lt;Role&gt;SM&lt;/Role&gt;
          &lt;Status&gt;Active&lt;/Status&gt;
      &lt;/Content&gt;
  .....
  &lt;/Message&gt;
  </code></pre>
  
  <p>Need to unmarshall the <code>&lt;Content&gt;</code> tag alone, by keeping the other XML part as same. Need to modify the elements in <code>&lt;Content&gt;</code> tag and bind the modified XML part with the original as shown below:</p>
  
  <p><strong>Expected Output XML:</strong> </p>
  
  <pre><code>&lt;Message&gt;
      &lt;x&gt;
      &lt;/x&gt;
      &lt;y&gt;
      &lt;/y&gt;
      &lt;z&gt;
      &lt;/z&gt;
      &lt;!-- Need to unmarshall this content to "Content" - java Object --&gt;
      &lt;Content&gt;
          &lt;Name&gt;Robin_123&lt;/Name&gt;
          &lt;Role&gt;Senior Member&lt;/Role&gt;
          &lt;Status&gt;1&lt;/Status&gt;
      &lt;/Content&gt;
  .....
  &lt;/Message&gt;
  </code></pre>
  
  <p><strong>My Questions:</strong></p>
  
  <ol>
  <li><p>What is the possible solution for this Requirement ? <strong><em>(Except <code>DOM</code> parsing - as XML contnet is very huge)</em></strong></p></li>
  <li><p>Is there any option to do this in <code>JAXB2.0</code> ?</p></li>
  </ol>
  
  <p>Please provide your suggestions on this.</p>