java 多线程操作同一个变量

例子，假设是个卖票系统，多个线程（例子中有2个线程）操作同一个变量ticketCount（余票的数量）。

Expected : 多个线程对同个变量会同步操作，不会造成混乱。

public class Test implements Runnable {

private String threadName;

private int ticketCount;

public Test(String threadName, int ticketCount) {

this.threadName = threadName;

this.ticketCount = ticketCount;

}

public synchronized int sellTicket() {

return ticketCount--;

}

@Override

public void run() {

// TODO Auto-generated method stub

while (ticketCount > 0) {

System.out.println(getThreadName() + " : " + sellTicket());

}

}

public String getThreadName() {

Thread a = Thread.currentThread();

return a.getName();

}

public static void main(String[] args) {

Test t1 = new Test("Ticket available ", 10);

Thread thread1 = new Thread(t1,

"1 window sell ticket ,ticket available ");

Thread thread2 = new Thread(t1,

"2 window sell ticket ,ticket available ");

thread1.start();

thread2.start();

}

}

----------------------打印结果（每次运行不一样）----------------------

2 window sell ticket ,ticket available : 9

2 window sell ticket ,ticket available : 8

2 window sell ticket ,ticket available : 7

2 window sell ticket ,ticket available : 6

2 window sell ticket ,ticket available : 5

2 window sell ticket ,ticket available : 4

1 window sell ticket ,ticket available : 10

2 window sell ticket ,ticket available : 3

1 window sell ticket ,ticket available : 2

2 window sell ticket ,ticket available : 1