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));
  }
}