// references/AddingClone.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// You must go through a few gyrations
// to add cloning to your own class
import java.util.*;
import java.util.stream.*;

class Int2 implements Cloneable {
 private int i;
 Int2(int ii) { i = ii; }
 public void increment() { i++; }
 @Override
 public String toString() {
 return Integer.toString(i);
 }
 @Override
 public Int2 clone() {
 try {
 return (Int2)super.clone();
 } catch(CloneNotSupportedException e) {
 throw new RuntimeException(e);
 }
 }
}

// Inheritance doesn't remove cloneability:
class Int3 extends Int2 {
 private int j; // Automatically duplicated
 Int3(int i) { super(i); }
}

public class AddingClone {
 @SuppressWarnings("unchecked")
 public static void main(String[] args) {
 Int2 x = new Int2(10);
 Int2 x2 = x.clone();
 x2.increment();
 System.out.println(
 "x = " + x + ", x2 = " + x2);
 // Anything inherited is also cloneable:
 Int3 x3 = new Int3(7);
 x3 = (Int3)x3.clone();
 ArrayList<Int2> v = IntStream.range(0, 10)
 .mapToObj(Int2::new)
 .collect(Collectors
 .toCollection(ArrayList::new));
 System.out.println("v: " + v);
 ArrayList<Int2> v2 =
 (ArrayList<Int2>)v.clone();
 // Now clone each element:
 IntStream.range(0, v.size())
 .forEach(i -> v2.set(i, v.get(i).clone()));
 // Increment all v2's elements:
 v2.forEach(Int2::increment);
 System.out.println("v2: " + v2);
 // See if it changed v's elements:
 System.out.println("v: " + v);
 }
}
/* Output:
x = 10, x2 = 11
v: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
v2: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
v: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
*/