package ifeve;

import java.util.concurrent.atomic.AtomicInteger;

/**
 * @Description
 * @Author msli
 * @Date 2021年10月13日
 */

public class InstructionReorderTest {

 private static int x = 0, y = 0;
 private static int a = 0, b = 0;

 private static boolean flag = true;

 public static void main(String[] args) throws InterruptedException {
 Method1();
 Method2();
 }

 private static void Method1() throws InterruptedException {
 int i = 0;
 for (;;) {
 i++;
 x = 0;
 y = 0;
 a = 0;
 b = 0;
 final Thread thread1 = new Thread(() -> {
 a = 1;
 x = b;
 });
 final Thread thread2 = new Thread(() -> {
 b = 2;
 y = a;
 });
 thread1.start();
 thread2.start();
 thread1.join();
 thread2.join();
 if (x==0 && y==0) {
 System.out.println("第"+i+"次调用 x==y==0");
 break;
 }
 }
 }

 public static void Method2() throws InterruptedException {
 int i = 0;
 while (true) {
 i++;
 a = 0;
 flag = false;
 Thread t1 = new Thread() {
 @Override
 public void run() {
 a = 1;
 flag = true;
 }
 };
 int finalI = i;
 Thread t2 = new Thread() {
 @Override
 public void run() {
 if (flag){
 if (a==0){
 System.out.format( "-----第%d次 发生指令重排序----- a = %d", finalI, a);
 }
 }
 }
 };
 t1.start();
 t2.start();
 t1.join();
 t2.join();
 }
 }
}