OnJava8-Examples/references/ImmutableInteger.java

// references/ImmutableInteger.java
// (c)2021 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.
// The Integer class cannot be changed
import java.util.*;
import java.util.stream.*;

public class ImmutableInteger {
  public static void main(String[] args) {
    @SuppressWarnings("deprecation")
    List<Integer> v = IntStream.range(0, 10)
      .mapToObj(Integer::new)
      .collect(Collectors.toList());
    System.out.println(v);
    // But how do you change the int
    // inside the Integer?
  }
}
/* Output:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
*/