private method in inheritance in Java

pei wang picture pei wang · Oct 19, 2013 · Viewed 27k times · Source

I have confusion about using private methods in inheritance, for example:

public class A {
    private void say(int number){
        System.out.print("A:"+number);

    }
}

public class B extends A{
    public void say(int number){
        System.out.print("Over:"+number);
    }
}

public class Tester {
    public static void main(String[] args) {

        A a=new B();
        a.say(12);

    }
}

Based on the codes above, I am confused about the inheritance of private method, is the private method inherited from class A to B? Or the say methods in both classes are totally unrelated? As the code has error when it is running in main() method, it seems like class B cannot invoke the private method from class A.

Answer

nhgrif picture nhgrif · Oct 19, 2013

If you want a subclass to have access to a superclass method that needs to remain private, then protected is the keyword you're looking for.

  • Private allows only the class containing the member to access that member.
  • Protected allows the member to be accessed within the class and all of it's subclasses.
  • Public allows anyone to access the member.