验证java 递增不是原子操作

如上代码

import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;public class AutoInc {public static int res = 0;public static int get() {res++;return res;}public static void main(String[] args) throws Exception {ExecutorService es = Executors.newFixedThreadPool(15);for (int i = 0; i < 15; i++) {es.submit(new Runnable() {@Overridepublic void run() {int myres = 0;for (int j = 0; j < 1000; j++) {myres = get();}System.out.println(Thread.currentThread() + " res:" + myres);}});}es.shutdown();Thread.sleep(1000 * 5);// while(!es.isTerminated()){//// }if (res != 15000) {System.out.println("finalCountL not matched." + res);}}}