模拟线程不安全的银行账户类

public class Test_09 {
    public static void main(String[] args) {
        Account account = new Account(1000);
        Thread t1 = new Thread(new AccountThread(account));
        Thread t2 = new Thread(new AccountThread(account));
        t1.start();
        t2.start();
    }
}

class AccountThread implements Runnable{
    private Account account;

    public AccountThread(Account account){
        this.account = account;
    }

    @Override
    public void run() {
        this.account.withdraw(1000);
    }
}

class Account{
    private double balance;

    public void withdraw(double money){
        double before = this.balance;
        double after = this.balance - money;
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        this.setBalance(after);
        System.out.println(Thread.currentThread().getName() + "取款成功，余额为" + this.getBalance());
    }

    @Override
    public String toString() {
        return "Account{" +
                "balance=" + balance +
                '}';
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }

    public Account() {
    }

    public Account(double balance) {
        this.balance = balance;
    }
}