public class Ticket implements Runnable {
private int ticket = 100;
@Override
public void run() {
while (true) {
if (ticket > 0) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(Thread.currentThread().getName() + "卖了一张票，剩下:" + ticket--);
}
}
}
public static void main(String[] args) {
Ticket ticket = new Ticket();
Thread t1 = new Thread(ticket, "窗口1");
Thread t2 = new Thread(ticket, "窗口2");
Thread t3 = new Thread(ticket, "窗口3");
t1.start();
t2.start();
t3.start();
}
}
此时会出现线程安全问题，可以加锁解决此问题
public class Ticket implements Runnable {
private int ticket = 100;
Object object = new Object();
@Override
public void run() {
while (true) {
if (ticket > 0) {
synchronized (this) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(Thread.currentThread().getName() + "卖了一张票，剩下:" + ticket--);
}
}
}
}
public static void main(String[] args) {
Ticket ticket = new Ticket();
Thread t1 = new Thread(ticket, "窗口1");
Thread t2 = new Thread(ticket, "窗口2");
Thread t3 = new Thread(ticket, "窗口3");
t1.start();
t2.start();
t3.start();
}
} 
还是出现了线程安全问题，这是为什么呢？
