使用同步块模拟同时取钱

/**
 *     使用同步块模拟同时取钱
 *
 */
public class SynMoney {
    public static void main(String[] args) {
        CountMoney countMoney = new CountMoney(1000);
        Peoples man = new Peoples(90, countMoney);
        Peoples woMan = new Peoples(80, countMoney);
        new Thread(man).start();
        new Thread(woMan).start();
    }
}

//账户金额
class CountMoney {
    public int money;
    public CountMoney(int money) {
        this.money = money;
    }
}
//取钱的人
class Peoples implements Runnable{
    private int payMoney;
    private CountMoney countMoney;
    
    public Peoples(int payMoney, CountMoney countMoney) {
        this.payMoney = payMoney;
        this.countMoney = countMoney;
    }

    @Override
    public void run() {
        test();
    }
    public void test() {
        synchronized(countMoney) {    //同步块
            if(countMoney.money-payMoney<0){
                return;
            }
            System.out.println("账户余额-->"+countMoney.money);
            countMoney.money -= payMoney;
            System.out.println("支取-->"+payMoney);
            System.out.println("账户剩余-->"+countMoney.money);
        }
    }
    
}

结果：

　　账户余额-->1000
　　支取-->90
　　账户剩余-->910
　　账户余额-->910
　　支取-->80
　　账户剩余-->830