Java8-Lock-No.06

import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.locks.StampedLock;public class Lock6 {    private static int count = 0;    public static void main(String[] args) {        ExecutorService executor = Executors.newFixedThreadPool(2);        StampedLock lock = new StampedLock();        executor.submit(() -> {            long stamp = lock.readLock();            try {                if (count == 0) {                    stamp = lock.tryConvertToWriteLock(stamp);                    if (stamp == 0L) {                        System.out.println("Could not convert to write lock");                        stamp = lock.writeLock();                    }                    count = 23;                }                System.out.println(count);            } finally {                lock.unlock(stamp);            }        });        ConcurrentUtils.stop(executor);    }}