从基类方法调用基类覆盖的函数 [英] Calling base class overridden function from base class method

问题描述

public class A {
    public void f1(String str) {
        System.out.println("A.f1(String)");
        this.f1(1, str);
    }

    public void f1(int i, String str) {
        System.out.println("A.f1(int, String)");
    }
}



public class B extends A {
    @Override
    public void f1(String str) {
        System.out.println("B.f1(String)");
        super.f1(str);
    }

    @Override
    public void f1(int i, String str) {
        System.out.println("B.f1(int, String)");
        super.f1(i, str);
    }
}


public class Main {
    public static void main(String[] args) {
        B b = new B();
        b.f1("Hello");
    }
}

我希望这段代码能输出:

I'm seeking that this code would output:

B.f1(String)
A.f1(String)
A.f1(int, String)

然而我得到:

B.f1(String)
A.f1(String)
B.f1(int, String)
A.f1(int, String)

我知道在 A.f1(String) 中 B 的this"上下文中是 B 的实例.我可以选择执行链 new B1().f1(String) -> (A's) f1(String) -> (A's) f1(int, String) 吗?

I understand that under the context of B "this" in A.f1(String) is B's instance. Do I have the option to do the chain new B1().f1(String) -> (A's) f1(String) -> (A's) f1(int, String) ?

这是一个理论问题，实际上解决方案显然是在 A 中实现 f1(String) 和 f1(int, String) 都会调用的私有函数.

This is a theoretical question, practically the solution would obviously be in A to implement a private function that both f1(String) and f1(int, String) would call.

谢谢，
马克西姆.

Thank you,
Maxim.

推荐答案

很遗憾，没有

我相信你知道，但为了完整性，我会明确说明 - 只有 2 个关键字来控制方法调用:

As i'm sure you're aware, but I'll state explicitly for completeness - there are only the 2 keywords to control the method invocation:

• this - this.method() - 从调用实例的类(实例的顶部"虚拟表 - 隐含默认值)开始寻找方法
• super - super.method() - 从定义调用方法的类的父类(调用类的父类的虚拟表 - 并非严格正确，但这样想更简单 - 谢谢@maaartinus)

• this - this.method() - looks for method starting from the invoking instance's class (the instance's "top" virtual table - implied default)
• super - super.method() - looks for method starting from the parent class of the class in which the invoking method is defined (the invoking class' parent's virtual table - not strictly true, but simpler to think of this way - thanks @maaartinus)

我可以想象另一个关键字(例如 current?)按照您的描述进行:

I can imagine another keyword (e.g. current?) do what you describe:

• current - current.method() - 从定义调用方法的类开始查找方法

• current - current.method() - looks for method starting from the class in which the invoking method is defined

但是 Java 没有这样的关键字(还没有?).

but Java doesn't have such a keyword (yet?).

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