java - 在抽象类中实现时降低 java 接口(interface)的可见性

Question

我有如下三个接口(interface)

interface CFL extends PowerSaver, LightingDevice{
    void showLifeTime();
    void getBrand();
}

interface PowerSaver {
    void showEcoRate();
}

interface LightingDevice {
    void doLight();
}

然后我创建一个名为 Philips 的抽象类来实现 CFL

public abstract class Philips implements CFL{
    void showLifeTime(){}; // Compiler says Cannot reduce the visibility of the inherited method from CFL.
    void showEcoRate(){};  // Compiler says Cannot reduce the visibility of the inherited method from CFL.
}

我的问题是为什么它说我无法降低从 CFL 继承的方法的可见性。而我还没有减少它？

Answer 1

接口(interface)实现必须是public。

要了解错误，请参阅 spec :

Every method declaration in the body of an interface is implicitly public.

因此，您实际上是在重写(或者在本例中是实现)public 方法。