code: public ProcessingInstruction createProcessingInstruction(
            String target, String data) throws DOMException
    {
  
      error(XMLErrorResources.ER_FUNCTION_NOT_SUPPORTED);
  
      return null;
    }
docs: Unimplemented. See org.w3c.dom.Document
  
  @param target Target for Processing instruction
  @param data Data for Processing instruction
  
  @return null
  
  @throws DOMException