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package algs34;
import java.util.Arrays;
import java.util.Objects;
import stdlib.*;
public class XStudent {
int i;
double d;
int[] a;
Object o;
public boolean equals(Object y) {
//Trace.draw ();
if (y == this) return true;
if (y == null) return false;
if (y.getClass() != this.getClass()) return false;
XStudent that = (XStudent) y;
if (Integer.compare (this.i, that.i) != 0) return false;
if (Double.compare (this.d, that.d) != 0) return false;
if (! Arrays.equals (this.a, that.a)) return false;
if (! Objects.equals (this.o, that.o)) return false;
// don't use ((this.o).equals(that.o)) unless you know that (this.o!=null)
return true;
}
public int hashCode() {
int h = 17;
h = 31 * h + Integer.hashCode (i);
h = 31 * h + Double.hashCode (d);
h = 31 * h + Arrays.hashCode (a);
h = 31 * h + Objects.hashCode (o);
// don't use (o.hashCode()) unless you know that (o!=null)
return h;
}
public XStudent (double d, int[] a, Object o) {
this.d = d;
this.a = a;
this.o = o;
}
public static void main (String[] args) {
//Trace.run ();
Object p = new Object ();
XStudent x = new XStudent (0.1, new int[] { 1,2,3 }, p);
XStudent y = new XStudent (0.1, new int[] { 1,2,3 }, p);
StdOut.format ("(x==y)=%b x.equals(y)=%b\n", x==y, Objects.equals(x,y));
StdOut.format ("x=%s Objects.hashCode(x)=%x\n", x, Objects.hashCode (x));
StdOut.format ("y=%s Objects.hashCode(y)=%x\n", y, Objects.hashCode (y));
}
}
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