多线程写法，消除同步bug

public class Demo01 implements Runnable {

private int ticket = 10;

@Override

public void run() {

for (int i = 0; i < 10; i++) {

synchronized (this) {

if (ticket > 0) {

try {

Thread.sleep(1000);

} catch (InterruptedException e) {

e.printStackTrace();

}

System.out.println(Thread.currentThread().getName()

+ ",正在卖出第" + (this.ticket--) + "张票！");

		}
	}
}

}

public static void main(String[] args) {

Demo01 mt = new Demo01();

new Thread(mt, "售票员A").start();

new Thread(mt, "售票员B").start();

new Thread(mt, "售票员C").start();

}