code: public static CmsXmlContent unmarshal(String xmlData, String encoding, EntityResolver resolver)
      throws CmsXmlException {
  
          return unmarshal(null, xmlData, encoding, resolver);
      }
docs: Factory method to unmarshal (generate) a XML content instance from a String
  that contains XML data.<p>
  
  The given encoding is used when marshalling the XML again later.<p>
  
  Since no {@link CmsObject} is available, no link validation is performed!<p>
  
  <b>Warning:</b><br/>
  This method does not support requested historic versions, it always loads the
  most recent version. Use <code>{@link #unmarshal(CmsObject, CmsResource, ServletRequest)}</code>
  for history support.<p>
  
  @param xmlData the XML data in a String
  @param encoding the encoding to use when marshalling the XML content later
  @param resolver the XML entity resolver to use
  
  @return a XML content instance unmarshalled from the String
  
  @throws CmsXmlException if something goes wrong