/** Tester routine for reversing arrays */
  public static void main(String args[]) {
    Integer[] a = {4, 8, 15, 16, 23, 42};  // autoboxing allows this
    String[] s = {"Jack", "Kate", "Hurley", "Jin", "Boone"};
    System.out.println("a = " + Arrays.toString(a));
    System.out.println("s = " + Arrays.toString(s));
    System.out.println("Reversing...");
    reverse(a);
    reverse(s);
    System.out.println("a = " + Arrays.toString(a));
    System.out.println("s = " + Arrays.toString(s));
  }