java里线程同步方法二：同步函数

class ThreadDemo1 {
public static void main(String[] args) {
TestThread tt = new TestThread();
new Thread(tt).start();
new Thread(tt).start();
new Thread(tt).start();
new Thread(tt).start();

}
}

class TestThread implements Runnable {
int tickets = 100;

public void run() {
while (true) {
sale();
}
}

public synchronized void sale() {
if (tickets > 0) {
try {
Thread.sleep(10);
} catch (Exception e) {
}
System.out.println(Thread.currentThread().getName()
+ " is saling ticket " + tickets--);
}
}
}