JMM volatile field demo

package ch.claude_martin.foo;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.ForkJoinPool;

public class MyClass {

    static class Car {
        private String owner = "N/A";

        public String getOwner() {
            return this.owner;
        }

        public void setOwner(String o) {
            this.owner = o;
        }
    }

    volatile Car car = null;

    public static void main(String args[]) throws InterruptedException {
        new MyClass().go();
    }

    void go() throws InterruptedException {

        ExecutorService es = ForkJoinPool.commonPool();
        Runnable taskA = () -> {
            car = null;
        };

        Runnable taskB = () -> {
            car = new Car();
            // we call yield() because it would be rather unlikely that the thread is
            // interrupted here. You can remove it, but it will take longer.
            Thread.yield();
            car.setOwner("Jane");
        };

        Runnable taskC = () -> {
            final Car copy = car; // taskA might set this to null at any time
            if (copy != null) {
                final String owner = copy.getOwner();
                if ("N/A".equals(owner)) {
                    System.err.println(owner);
                    System.exit(0);// Stop the VM because we got to read the initial value
                }
                // else System.out.println(owner);
            }
        };

        while (true) {
            es.submit(taskA);
            es.submit(taskB);
            es.submit(taskC);
        }
    }
}