code: @Override
      protected String getReturnParams() {
          rules_returnParams.putIfAbsent(getClass(), new ConcurrentHashMap<>());
          Map<String, String> methodName_returnParams = rules_returnParams.get(getClass());
          String returnParams = methodName_returnParams.get(next);
          if (returnParams == null) {
              ReturnParams returnParamsAnnotation = getMethod().getDeclaredAnnotation(ReturnParams.class);
              LOG.info(String.format("[RuleController] %s 的 returnParams = %s", next, returnParamsAnnotation == null ? "" : returnParamsAnnotation.value()));
              methodName_returnParams.put(next, returnParamsAnnotation == null ? "" : returnParamsAnnotation.value());
          }
          return methodName_returnParams.get(next);
      }
docs: 懒加载