线程并发：银行解决

*同步代码块：synchronized (Obj){执行体…}

* Obj称之为同步监视器，可以是任何对象，但是推荐使用共享资源作为同步监视器。

*不同方法中无需指定同步监视器，因为同步方法中的同步监视器就是this，就是这个对象本身，或者是class。

public class MyBank2{

public static void main(String[] args) throws InterruptedException {

Account2 account = new Account2(1000, "旅游基金");

new Bank2(account, 500, "你").start();

new Bank2(account, 600, "女朋友").start();

}

}

//账户

class Account2 {

//账户总余额

int money;

//账户名

String name;

public Account2(int money, String name) {

this.money = money;

this.name = name;

}

}

//银行

class Bank2 extends Thread{

//客户账户

Account2 account;

//取得钱数

int drawingMoney;

public Bank2(Account2 account, int drawingMoney, String name) {

super(name);

this.account = account;

this.drawingMoney = drawingMoney;

}

@Override

public void run() {

synchronized (account) {

if (account.money- drawingMoney < 0) {

return;

}

try {

Thread.sleep(500);

} catch (InterruptedException e) {

e.printStackTrace();

}

//卡内余额 = 余额 - 取得钱

account.money = account.money - drawingMoney;

}

}

}