如何使外部类继承自内部类？ [英] How to make an outer class inherited from an inner class?

问题描述

我怎样才能做出类似的工作：

How can I make something like this work:

class Outer {
  int some_member;

  abstract class InnerBase {
    abstract void method();
  }
}

class OuterExtendsInner extends Outer.InnerBase {
  OuterExtendsInner(Outer o) { o.super(); }
  void method() {
    // How do I use some_member here?
    // Writing Outer.this.some_member -> error about Outer not being an enclosing class
    // Writing just some_member -> no-go, either
  }
}

解决方法是拥有一个在InnerBase中返回Outer.this并从派生类调用THAT的方法，但还有另一种方法吗？

The workaround is to have a method in InnerBase that returns Outer.this and call THAT from derived classes, but is there another way?

我主要想从外面扩展InnerBase以便更好代码组织，但我可以将所有派生类移动到外部。

I primarily want to extend the InnerBase from outside in order to have better code-organization, but I could move all derived classes into Outer.

推荐答案

这里的问题是链接的合成字段 InnerBase 到外部是私有字段。因此，我们只能从 InnerBase 中访问外部对象，或者如果某个方法或字段提供对同一对象的引用。

The problem here is that the synthetic field which links InnerBase to Outer is a private field. Thus, we can only access the outer object from within InnerBase, or if some method or field there provides a reference to the same object.

这篇关于如何使外部类继承自内部类？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！