java练习题-银行客户

package main;
import java.util.ArrayList;
/**
 * （10分）
 * 做一个简单的银行、账户演示程序。
 * （1）定义一个账户类，包含用户名、密码、余额等属性、存钱、取钱等方法。
 * （2）定义一个银行类，包含银行名、账户列表等属性，开账户、查账户的功能。账户列表可以使用集合相关的类，
 *      如ArrayList，最好同时使用泛型。
 * （3）定义一个测试类及main函数，在其中创建一个银行，开设一些账号，模拟存钱、取钱、显示余额等。
 */
public class Main {
    public static void main(String[] args){
        Bank bank = new Bank("HDBank");
        bank.openAccount("xiaoming","666",0);
        bank.openAccount("xiaoli","777",0);
        bank.openAccount("xiaohong","888",0);
        bank.saveMoney("xiaoli",100);
        //向特定账户存钱
        bank.drawMoney("xiaoli",50,"777");
        //从特定账户取钱,需验证密码
        bank.showAccount("xiaoli");
        //显示xiaoli账户信息
        bank.drawMoney("xiaoli",100,"a wrong password");
        //密码错误，取钱失败的情况
        bank.drawMoney("xiaoli",100,"777");
        //余额不足的情况
    }
}

class Account{
    private String userName;
    private String password;
    private double balance;
    Account(String userName,String password,double balance){
        this.userName = userName;
        this.password = password;
        this.balance = balance;
    }
    public void save(double money){
        //存钱
        balance += money;
        System.out.printf("%s存了%.2f元，账户余额为%.2f元。\n",userName,money,balance);
    }
    public void draw(double money){
        //取钱，若账户余额不足，则不能取钱
        if(balance - money <= 0) {
            System.out.printf("%s取钱%.2f，账户余额为%.2f元。",userName,money,balance);
            System.out.println("余额不足，取钱失败。");
        }else {
            balance -= money;
            System.out.printf("%s取了%.2f元，账户余额为%.2f元。\n", userName, money, balance);
        }
    }
    public void show(){
        //显示账户信息
        System.out.printf("userName:%s\n",userName);
        System.out.printf("balance:%.2f\n",balance);
    }
    public String getUserName(){
        //得到用户名
        return userName;
    }
    public String getPassword(){
        //得到密码
        return password;
    }
    public String getInfo(){
        //返回账户信息
        return "userName:"+userName+",banlance:"+balance;
    }
}

class Bank{
    public String bankName;
    private ArrayList accounts;
    Bank(String bankName){
        this.bankName=bankName;
        accounts=new ArrayList();
    }
    Bank(String bankName,ArrayList accounts){
        this.bankName=bankName;
        this.accounts=accounts;
    }
    public void openAccount(String userName,String password,double balance){
        //开账户
        accounts.add(new Account(userName,password,balance));
    }
    public Account seekAccount(String userName){
        //查找账户按用户名,若找到，返回该账户，否则，返回null
        for(Account account:accounts){
            if(userName.equals(account.getUserName()))
                return account;
        }
        return null;
    }
    public void showAccount(String userName){
        Account account=seekAccount(userName);
        if(account==null)
            System.out.println("该账户不存在。");
        else
            account.show();
    }
    public void saveMoney(String userName,double money){
        //向特定账户存钱
        Account account = seekAccount(userName); //查找
        if(account==null)
            System.out.println("该账户不存在。");
        else
            account.save(money);
    }
    public void drawMoney(String userName,double money,String password){
        //从特定账户取钱,需验证密码
        Account account = seekAccount(userName); //查找
        if(account==null)
            System.out.println("该账户不存在。");
        else {
            if(password.equals(account.getPassword())) {
                account.draw(money);
            }else {
                System.out.println("密码不正确，取钱失败。");
            }
        }
    }
}