Question

I came across this scenario. We have a class lets say Main having a private method print. There is another class Main1 which extends Main class and redefines the print method. Since main1 is an object of Main1 class, I expect main1 print method to get called…

public class Main {
    public static void main(String[] args) {
       Main main1 = new Main1();
       List<String> list = new ArrayList<String>();
       main1.print(list);
    }

    private void print(List<String> string) {
       System.out.println("main");
    }

}

class Main1 extends Main {
    public void print(List<String> string) {
       System.out.println("main1");
    }
}

In this case, when we run the program, it print “main”. It really confuses me as that method is private and is not even part of Main1 class.

Answer 1

The answer is not too hard:

• the type of the main1 variable is Main (not Main1)
• so you can only call methods of that type
• the only possible method called print that accepts a List<String> on Main is the private one
• the calling code is inside the class Main so it can call a private method in that class

Therefore Main.print(List<String>) will be called.

Note that changing the type of main1 to Main1 will result in the other print(List<String>) method being called.