源码地址

源码阅读仓库: [SourceHot](https://github.com/SourceHot/spring-framework-read)

org.springframework.core.annotation.OrderUtils主要方法如下

getOrder getPriority

测试类

org.springframework.core.annotation.OrderUtilsTests

@Nullable
    public static Integer getOrder(Class<?> type) {
        // 缓存中获取
        Object cached = orderCache.get(type);
        if (cached != null) {
            // 返回 int
            return (cached instanceof Integer ? (Integer) cached : null);
        }
        /**
         * 注解工具类,寻找{@link Order}注解
         */
        Order order = AnnotationUtils.findAnnotation(type, Order.class);
        Integer result;
        if (order != null) {
            // 返回
            result = order.value();
        } else {
            result = getPriority(type);
        }
        // key: 类名,value: intValue
        orderCache.put(type, (result != null ? result : NOT_ANNOTATED));
        return result;
    }

@Nullable
  public static Integer getPriority(Class<?> type) {
      if (priorityAnnotationType == null) {
          return null;
      }
      // 缓存中获取
      Object cached = priorityCache.get(type);
      if (cached != null) {
          // 不为空返回
          return (cached instanceof Integer ? (Integer) cached : null);
      }
      // 注解工具获取注解
      Annotation priority = AnnotationUtils.findAnnotation(type, priorityAnnotationType);
      Integer result = null;
      if (priority != null) {
          // 获取 value
          result = (Integer) AnnotationUtils.getValue(priority);
      }
      // 向缓存插入数据
      priorityCache.put(type, (result != null ? result : NOT_ANNOTATED));
      return result;
  }