code: public void warning(Element e, String key, Object... args) {
          if (configuration.showMessage(e, key)) {
              report(WARNING, e, resources.getText(key, args));
          }
      }
docs: Reports a warning message to the doclet's reporter.
  
  @param e an element identifying the declaration whose position should
  to be included with the message
  @param key the name of a resource containing the message to be printed
  @param args optional arguments to be replaced in the message.