Question

public class A {
    public void f1(String str) {
        System.out.println("A.f1(String)");
        this.f1(1, str);
    }

    public void f1(int i, String str) {
        System.out.println("A.f1(int, String)");
    }
}



public class B extends A {
    @Override
    public void f1(String str) {
        System.out.println("B.f1(String)");
        super.f1(str);
    }

    @Override
    public void f1(int i, String str) {
        System.out.println("B.f1(int, String)");
        super.f1(i, str);
    }
}


public class Main {
    public static void main(String[] args) {
        B b = new B();
        b.f1("Hello");
    }
}

I’m seeking that this code would output:

B.f1(String)
A.f1(String)
A.f1(int, String)

Yet I’m getting:

B.f1(String)
A.f1(String)
B.f1(int, String)
A.f1(int, String)

I understand that under the context of B “this” in A.f1(String) is B’s instance.
Do I have the option to do the chain new B1().f1(String) -> (A’s) f1(String) -> (A’s) f1(int, String) ?

This is a theoretical question, practically the solution would obviously be in A to implement a private function that both f1(String) and f1(int, String) would call.

Thank you,
Maxim.

Answer 1

Unfortunately, no

As i’m sure you’re aware, but I’ll state explicitly for completeness – there are only the 2 keywords to control the method invocation:

• this – this.method() – looks for method starting from the invoking instance’s class (the instance’s “top” virtual table – implied default)
• super – super.method() – looks for method starting from the parent class of the class in which the invoking method is defined (the invoking class’ parent’s virtual table – not strictly true, but simpler to think of this way – thanks @maaartinus)

I can imagine another keyword (e.g. current?) do what you describe:

• current – current.method() – looks for method starting from the class in which the invoking method is defined

but Java doesn’t have such a keyword (yet?).