Java重载和继承方法选择

Question

让我们研究以下代码:

public class App {

    public static class A {

        public void doSmth3(long a) {
            System.out.println("This is doSmth3() in A...");
        }
    }

    public static class B extends A {

        public void doSmth3(int a) {
            System.out.println("This is doSmth3() in B...");
        }
    }

    public static void test(A a) {
        a.doSmth3(1);
    }

    public static void main(String[] args) {
       test(new B());
        new B().doSmth3(3);
    }

}

输出继电器:

This is doSmth3() in A...
This is doSmth3() in B...

从我这边2线主要应该提供相同的结果但结果是不同的.

我的意见This is doSmth3() in A...应该输出twise,因为它正在超载.

请解释输出

Answer 1

简单:当Java编译器看到对a.doSmth3(1)内部的调用时test(A),它只能将其编译为调用A#doSmth3(long),这是唯一可用的方法.请注意,B#doSmth3(int)是超负荷的A#doSmth3(long),而不是替代.