Is it allowed to inherit private methods?

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"public static class CheapCar { private void printlnDesire()" "public static class GeoMetro extends CheapCar { public void printlnDesire()" I thought that private methods can not be inherited. Why it is written this way?

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Anonymous #11267629 (Anouk)

Level 23 , Netherlands

Expert

2 June, 12:48

You cannot inherit private methods, because the class cannot access these methods directly.

Thomas

Level 41 , Bayreuth, Germany

27 May, 07:37

You can not inherit private methods. However you can write a method with the same name in a descendant class. But that method isn't polymorphic.

public class Polymorphism {
    public static void main(String[] args) throws IOException {

        // create a Child object and assign it to a Parent reference variable.
        Parent object = new Child();
        // invoking printA on object. Here you'll see polymorphism in action. The object knows it is a Child
        // and the child method printA is used. That's the expected behaviour, A-child.
        object.printA();
        // now invoking printB on object. Now the output is B-parent. That's unexpected. And that's because it is not
        // possible to override a private (or final -> but compile time error) method
        object.printB();
        // to call the Child class' printB method you'd need to cast to Child and then call printB
        ((Child) object).printB();

        // as a sidenote, instance variables aren't polymorph. Means they act like the private method and you should
        // avoid to have fields with the same names in parent and children
    }

    static class Parent {

        public void printA() {
            System.out.println("A-parent");
        }

        private void printB() {
            System.out.println("B-parent");
        }
    }

    static class Child extends Parent {
        @Override
        public void printA() {
            System.out.println("A-child");
        }

        public void printB() {
            System.out.println("B-child");
        }
    }
}