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package com.lovo;import java.io.FileReader;import java.io.FileWriter;import java.util.Properties;import javax.swing.JOptionPane;public class ATM {	public static void main(String[] args) {		login();	}	/*	 * 登陆	 */	public static void login() {		JOptionPane.showMessageDialog(null, "欢迎光临");		String s= getdata("userName.txt","用户名");		String sp= getdata("psw.txt","密码");		int i = 0;		for (i = 0; i < 3; i++) {			String str1 = JOptionPane.showInputDialog(null, "请输入用户名");			String str2 = JOptionPane.showInputDialog(null, "请输入密码");			if (str1.equals(s) && str2.equals(sp)) {				JOptionPane.showMessageDialog(null, "登陆成功");				break;			} else {				JOptionPane.showMessageDialog(null, "用户名或密码错误");			}		}		if (i == 3) {			JOptionPane.showMessageDialog(null, "非法用户");		} else {			while (true) {				String str = JOptionPane.showInputDialog(null, "1、存款" + "\n"						+ "2、取款" + "\n" + "3、查询" + "\n" + "4、改密" + "\n"						+ "5、退出");				int type = Integer.parseInt(str);				if (type == 1) {					saveMoney();				}				if (type == 2) {					getMoney();				}				if (type == 3) {					getInfo();				}				if (type == 4) {					changPassWord();				}				if (type == 5) {					break;				}			}		}	}/* * 存钱 */	public static void saveMoney() {		String str = JOptionPane.showInputDialog(null, "请输入存款金额");		int money = Integer.parseInt(str);		String sp= getdata("money.txt","money");		int a = Integer.parseInt(sp);		a = a + money;		setdata("money",a+"","money.txt");	}/* * 取钱 */	public static void getMoney() {		String str = JOptionPane.showInputDialog(null, "请输入取款金额");		int money = Integer.parseInt(str);		String s=getdata("money.txt","money");		int a = Integer.parseInt(s);		if (a < money) {			JOptionPane.showMessageDialog(null, "账号已超支");		} else {			int b = a - money;			setdata("money",b+"","money.txt");		}	}/* * 查询余额 */	public static void getInfo() {		String s =getdata("money.txt","money");		JOptionPane.showMessageDialog(null, "账号余额为" + s);	}/* * 修改密码 */	public static void changPassWord() {		String str1 = JOptionPane.showInputDialog(null, "请输入新密码");		String str2 = JOptionPane.showInputDialog(null, "请确认新密码");		if (str1.equals(str2)) {			setdata("密码",str1,"psw.txt");		}		else{			JOptionPane.showMessageDialog(null, "两次输入密码不一致");		}	} /* * 获取数据 */ public static String getdata(String s,String p){	 Properties pro = new Properties();		try {			pro.load(new FileReader(s));		} catch (Exception e) {			System.out.println("文件不存在");		}		String st = pro.getProperty(p); 		return st; } /*  * 保存数据  */ public static void setdata(String s,String p,String q){	 Properties pro = new Properties();	 pro.setProperty(s, p);		try {			pro.store(new FileWriter(q), null);		} catch (Exception e) {			System.out.println("文件不存在");		} }}

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