code: public static <T> T unmarshal(final String xmlData, final Class<?>... classesToBeBound) {
          return unmarshal(xmlData, null, classesToBeBound);
      }
docs: Unmarshals the given data. A <code>null</code> XML data argument returns <code>null</code>.
  
  @param xmlData
  XML data or <code>null</code>.
  @param classesToBeBound
  List of java classes to be recognized by the {@link JAXBContext} - Cannot be <code>null</code>.
  
  @return Data or <code>null</code>.
  
  @param <T>
  Type of the expected data.