code: private SofaRpcException cannotFoundServiceMethod(String appName, String serviceName, String methodName) {
          String errorMsg = LogCodes.getLog(
              LogCodes.ERROR_PROVIDER_SERVICE_METHOD_CANNOT_FOUND, serviceName, methodName);
          LOGGER.errorWithApp(appName, errorMsg);
          return new SofaRpcException(RpcErrorType.SERVER_NOT_FOUND_INVOKER, errorMsg);
      }
docs: 找不到服务方法
  
  @param appName     应用
  @param serviceName 服务
  @param methodName  方法名
  @return 找不到服务方法的异常