//
// still buggy (e.g. no NULL test)
//

import java.util.Vector;

class A { 
    public int a;
    public A(int i) { a = i;}
    public boolean equals(Object o) {
	return ((getClass() == o.getClass()) && 
		equalDF(o));
    }
    public boolean equalDF(Object o) {
	return (a == ((A) o).a);}
}

class B extends A { 
    public int b;
    public B(int i, int j) {super(i); b = j;}

    public boolean equalDF(Object o) {
	return ((b == ((B) o).b) && super.equalDF(o));
    }
}

class C extends B { 
    public int c;
    public C(int i, int j, int k) {super(i,j); c = k;}

    public boolean equalDF(Object o) {
	return ((c == ((C) o).c) && super.equalDF(o));
    }
}

public class EqualsTest5 {
    public static void main(String[] args) {
	A a1 = new A(1);
	B b1 = new B(1,1);
	C c1 = new C(1,1,1);
	
	System.out.println("a1.equals(b1) = " + a1.equals(b1));
	System.out.println("a1.equals(c1) = " + a1.equals(c1));
	System.out.println("b1.equals(a1) = " + b1.equals(a1));
	System.out.println("b1.equals(c1) = " + b1.equals(c1));
	System.out.println("c1.equals(a1) = " + c1.equals(a1));
	System.out.println("c1.equals(b1) = " + c1.equals(b1));

	System.out.println("a1.equals(a1) = " + a1.equals(a1));
	System.out.println("b1.equals(b1) = " + b1.equals(b1));
	System.out.println("c1.equals(c1) = " + c1.equals(c1));

	Vector v1 = new Vector(10000);
	Vector v2 = new Vector();
	System.out.println("v1.equals(v2) = " + v1.equals(v2));

	v1.add(new Integer(1));
	v1.add(new Integer(2));

	v2.add(new Integer(1));
	v2.add(new Integer(2));

	System.out.println("v1.equals(v2) = " + v1.equals(v2));
	System.out.println("v1.elementAt(0) == v2.elementAt(0) = " + 
			   (v1.elementAt(0) == v2.elementAt(0)));
    }
}