为什么当子类已经覆盖它时,调用父类的静态方法？

Question

当在子类中重写静态方法时,我对它的行为感到困惑.

以下是代码:

public class SuperClass {

    public static void staticMethod() {
        System.out.println("SuperClass: inside staticMethod");
    }
}

public class SubClass extends SuperClass {

//overriding the static method
    public static void staticMethod() {
        System.out.println("SubClass: inside staticMethod");
    }
}


public class CheckClass {

    public static void main(String[] args) {

        SuperClass superClassWithSuperCons = new SuperClass();
        SuperClass superClassWithSubCons = new SubClass();
        SubClass subClassWithSubCons = new SubClass();

        superClassWithSuperCons.staticMethod();
        superClassWithSubCons.staticMethod();
        subClassWithSubCons.staticMethod();

    }
}


Below is the output which we are getting :

    1) SuperClass: inside staticMethod
    2) SuperClass: inside staticMethod
    3) SubClass: inside staticMethod

为什么在第二种情况下会调用超类的静态方法？

如果方法不是静态的,那么根据多态性,在运行时传递子类对象时会调用子类的方法.

Answer 1

静态方法解析始终基于Reference类型.
代码

superClassWithSuperCons.staticMethod();
superClassWithSubCons.staticMethod();
subClassWithSubCons.staticMethod();

编译后转换为this

SuperClass.staticMethod();
SuperClass.staticMethod();
SubClass.staticMethod();

对此进行控制是调用SuperClass方法而不是子类方法.所以你得到SuperClass方法的输出.