为什么一个类不能被定义为protected？ [英] why a class cannot be defined as protected?

问题描述

我知道这是一个愚蠢的问题，但仍然有一个疑问，需要清除。

我的问题是为什么我们不能将类定义为protected。

我知道我们不能为什么？应该有一些具体的原因。

解决方案

因为没有意义。

受保护的类成员（方法或变量）就像package-private（默认可见性），除了它也可以从子类访问。

因为没有'subpackage'或' package-inheritance'in Java，声明类protected或package-private将是同样的事情。

你可以声明嵌套和内部类为protected或private。 / p>

I know this is a stupid question, but still i have a doubt which needs to be cleared.

My question is why cannot we define a class as protected.

I know we cannot but why? There should be some specific reason.

解决方案

Because it makes no sense.

Protected class member (method or variable) is just like package-private (default visibility), except that it also can be accessed from subclasses.
Since there's no such concept as 'subpackage' or 'package-inheritance' in Java, declaring class protected or package-private would be the same thing.

You can declare nested and inner classes as protected or private, though.

这篇关于为什么一个类不能被定义为protected？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！