OnJava8-Examples/reuse/Jurassic.java

// reuse/Jurassic.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.
// Making an entire class final

class SmallBrain {}

final class Dinosaur {
  int i = 7;
  int j = 1;
  SmallBrain x = new SmallBrain();
  void f() {}
}

//- class Further extends Dinosaur {}
// error: Cannot extend final class 'Dinosaur'

public class Jurassic {
  public static void main(String[] args) {
    Dinosaur n = new Dinosaur();
    n.f();
    n.i = 40;
    n.j++;
  }
}