if ("".equals(key)) { throw new IllegalArgumentException("The default prefix should represented as null rather than as a zero length String"); }
      public Object put(Object key, Object value)      {        if (value == null)        {          value = "";        }        Object result = super.put(key, value);        if (!isReconciling)        {          Element theElement = getElement();          if (theElement != null)          {              String xmlnsAttribute = "xmlns";              if (key != null)              {                xmlnsAttribute += ":" + key;              }              theElement.setAttributeNS(XSDConstants.XMLNS_URI_2000, xmlnsAttribute, (String)value);          }        }        return result;      }