案例1：模拟银行新用户现金业务办理

实验内容：

1) 银行新用户开户

2) 欢迎用户光临和欢迎用户下次光临

3) 存钱

4) 取钱

案例代码：

Bank类：

package cn.Bank;

public class Bank {
	static String Name;
	private String name;
	private String pswd;
	private double balance;
	private double turnover;

	// 静态方法
	static void welcome() {
		System.out.println("欢迎来到" + Name + "------------");
	}

	public Bank(String name, String pswd, double turnover) {
		super();
		this.name = name;
		this.pswd = pswd;
		this.balance = turnover - 10;
		this.turnover = turnover;
		System.out.println(name + "开户成功，余额" + balance);
	}

	// 存钱
	public void Save_money(double turnover) {
		balance = balance + turnover;
		System.out.println(name + "您好，您已存入" + turnover + "元，当前余额是" + balance + "元。");
	}

	// 取钱
	public void Withdraw_money(String pswd, double turnover) {
		if (this.pswd != pswd) {
			System.out.println("您输入的密码有误");
			return;
		}
		// 钱是否够
		if (this.balance < turnover) {
			System.out.println("您的余额不足");
		} else {
			balance = balance - turnover;
			System.out.println(name + "您好，您的帐户已取出" + turnover + "元，您的帐户余额是" + balance + "元");
		}
	}

	// 欢迎下次光临
	static void welcomeNext() {
		System.out.println("欢饮下次光临" + Name + "------------");
	}
}

Test类：

package cn.Bank;

public class Test {

	public static void main(String[] args) {
		Bank.Name = "中国人民银行";
		Bank.welcome();
		Bank bank = new Bank("李小小", "123456", 100);
		bank.Save_money(100);
		bank.Withdraw_money("123456", 50);
		bank.Withdraw_money("654321", 200);
		bank.Withdraw_money("123456", 50);
		Bank.welcomeNext();
	}
}

运行结果示例：

案例2：USB接口程序设计

实验内容：

1) 模拟往计算机的USB接口的插入设备；

2) 模拟开机时各USB接口的设备开始工作；

3) 模拟关机时各USB接口的设备停止工作。

案例代码：

Computer类：

package cn.usb;

public class Computer {
	private USB[] usbArr = new USB[4];

	public void add(USB usb) {
		for (int i = 0; i < usbArr.length; i++) {
			if (usbArr[i] == null) {
				usbArr[i] = usb;
				break;
			}
		}
	}

	public void powerOn() {
		for (int i = 0; i < usbArr.length; i++) {
			if (usbArr[i] != null) {
				usbArr[i].turnOn();
			}
		}
		System.out.println("电脑开机成功");
	}

	public void powerOff() {
		for (int i = 0; i < usbArr.length; i++) {
			if (usbArr[i] != null) {
				usbArr[i].turnOff();
			}
		}
		System.out.println("电脑关机成功");
	}

}

KeyBoard类：

package cn.usb;

public class KeyBoard implements USB {

	@Override
	public void turnOn() {
		// TODO Auto-generated method stub
		System.out.println("键盘启动了");
	}

	@Override
	public void turnOff() {
		// TODO Auto-generated method stub
		System.out.println("键盘关闭了");
	}
}

Microphone类：

package cn.usb;

public class Microphone implements USB {

	@Override
	public void turnOn() {
		// TODO Auto-generated method stub
		System.out.println("麦克风启动了");
	}

	@Override
	public void turnOff() {
		// TODO Auto-generated method stub
		System.out.println("麦克风关闭了");
	}

}

Mouse类：

package cn.usb;

public class Mouse implements USB {

	@Override
	public void turnOn() {
		// TODO Auto-generated method stub
		System.out.println("鼠标启动了");
	}

	@Override
	public void turnOff() {
		// TODO Auto-generated method stub
		System.out.println("鼠标关闭了");
	}
}

USB类：

package cn.usb;

public interface USB {
	void turnOn();

	void turnOff();
}

Test类：

package cn.usb;

public class Test {
	public static void main(String[] args) {
		Computer c = new Computer();
		c.add(new Mouse());
		c.add(new Microphone());
		c.add(new KeyBoard());
		c.powerOn();
		System.out.println("----------------");
		c.powerOff();
	}
}

运行结果示例：

案例3：身份证校验位和身份提取

实验内容：

1）从键盘上输入身份证的前17份

2）计算身份证的检验码

十七位数字id[17]本体码加权求和公式: S=Sum (Ai*Wi) ,i=0…..16。

其中,Ai表示身份证号码第i位的数字

wi表示第i位的加权因子，分别为{7 ,9,10,5,8,4,2,1,6,3,7,9,10,5,8,4,2}

先对前17位数字按位权求和，计算除以11的余数: y= S%11

通过模得到对应的末位校验码v[11]={‘1′ ,’0′,’x’,’9′,’8′,’7′,’6′,’5′,’4′, ‘3’,’2’}

3）判断性别

通过第17位数除以2的余数判断性别（1为男，0为女）

案例代码：


package cn.idcard;

import java.time.LocalDate;
import java.util.Scanner;

public class Test {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入身份证号的前17位：");
		String s = sc.nextLine();
		int[] a = { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 };
		char[] b = { '1', '0', 'x', '9', '8', '7', '6', '5', '4', '3', '2' };
		int sum = 0, n;
		for (int i = 0; i <= 16; i++) {
			n = s.charAt(i) - '0';
			sum = sum + n * a[i];
		}
		char c = b[sum % 11];
		System.out.println("末尾校验位为：" + c);
		String yString = s.substring(6, 10);
		String mString = s.substring(10, 12);
		String dString = s.substring(12, 14);
		int y = Integer.parseInt(yString);
		int m = Integer.parseInt(mString);
		int d = Integer.parseInt(dString);
		LocalDate localDate = LocalDate.of(y, m, d);
		System.out.println("出生年月日为：" + localDate.toString());
		int age = 2022 - y;
		int i = s.charAt(16) - '0';
		String sex = (i % 2) == 1 ? "男" : "女";
		System.out.println("您的年龄为：" + age + "性别为：" + sex);
	}
}

运行结果示例：