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Java casting question

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From	Chad <cdalten@gmail.com>
Newsgroups	comp.lang.java.programmer
Subject	Java casting question
Date	Wed, 12 Oct 2011 18:27:29 -0700 (PDT)
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Given the following...

class X {
    void f1() { System.out.println("XXX");}
    void f2() { System.out.println("AAA"); f1();}
}

class Y extends X {
    void f1() { System.out.println("YYY"); }
}

class Z extends X {
    void f1() { System.out.println("ZZZ"); }
}
public class Main {

    static void g(X a) {
        a.f2();
    }
    public static void main(String[] args) {
        X x = new X();
        Y y = new Y();
        Z z = new Z();

        Object obj = new Y();
        ((X) obj).f2();
        g(z);
        //y = (Y)x;
    }

}

I get the following output..

AAA
YYY
AAA
ZZZ


The question is about

Object obj = new Y();
((X) obj).f2();


How come YYY, but not XXX, gets printed on the second line? Both f1()
and f2() are in class X. So shouldn't f1() also have been casted to
(type) X?

Chad

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Thread

Java casting question Chad <cdalten@gmail.com> - 2011-10-12 18:27 -0700
  Re: Java casting question Arne Vajhøj <arne@vajhoej.dk> - 2011-10-12 21:36 -0400
    Re: Java casting question Lew <lewbloch@gmail.com> - 2011-10-12 19:05 -0700
      Re: Java casting question Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-10-13 10:24 +0000
  Re: Java casting question Travers Naran <tnaran@gmail.com> - 2011-10-12 23:40 -0700

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