code: public void setResult(Result result) throws IllegalArgumentException
    {
      if(null == result)
        throw new IllegalArgumentException(XSLMessages.createMessage(XSLTErrorResources.ER_RESULT_NULL, null)); //"Result should not be null");        
      m_result = result;
    }
docs: Enables the user of the TransformerHandler to set the
  to set the Result for the transformation.
  
  @param result A Result instance, should not be null.
  
  @throws IllegalArgumentException if result is invalid for some reason.