为什么我可以访问封闭类引用的私有成员 [英] Why can I access the private members of an enclosing class reference

问题描述

我已经看到很多关于访问封闭类的私有成员的问题。但是，我的问题恰恰相反。

I have seen many questions about accessing private members of an enclosing class. However, my question is the opposite.

如果我有（作为例子），则代码如下：

If I have (as an example), the following code:

public class A {

   private String outerString = "silly string";

   static class B {
      private final A someA = new A();      

      public void foo() {
         String b = someA.outerString ;
      }
   }
}

我想知道为什么会这样编译？我希望通过我从类A（通过someA.outerString）访问'outerString'实例变量的方式来预测错误。我知道内部类可以通过隐式的this引用直接访问封闭的类成员。但是在这里，B类是静态的，所以'this'引用不适用。

I'm wondering why this compiles? I would have expected an error by virtue of the way in which I am accessing the 'outerString' instance variable from class A (via someA.outerString). I know that an inner class can access the enclosing class members directly by an implicit 'this' reference. But here, class B is static, so the 'this' reference won't apply.

推荐答案

B 是 A的成员因此可以访问 A 的私有字段和方法。

在这种情况下，虽然 B 是 static 但它正在使用A的实例访问字段 A.outerString 。

B is a member of A and therefore has access to A's private fields and methods.
In this case, although B is static it is using an instance of A to access the field A.outerString.

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