银行管理系统C++代码转Java代码4_9

C++代码源自《C++语言程序设计(第4版)》(清华大学计算机系列教材) 郑莉, 董渊, 何江舟 清华大学出版社
4_9

C++源码

//4_9.cpp
#include <iostream>
#include <cmath>
using namespace std;

class SavingsAccount { //储蓄账户类
private:
	int id;				//账号
	double balance;		//余额
	double rate;		//存款的年利率
	int lastDate;		//上次变更余额的时期
	double accumulation;	//余额按日累加之和

	//记录一笔帐，date为日期，amount为金额，desc为说明
	void record(int date, double amount);
	//获得到指定日期为止的存款金额按日累积值
	double accumulate(int date) const {
		return accumulation + balance * (date - lastDate);
	}
public:
	//构造函数
	SavingsAccount(int date, int id, double rate);
	int getId() { return id; }
	double getBalance() { return balance; }
	double getRate() { return rate; }

	//存入现金
	void deposit(int date, double amount);
	//取出现金
	void withdraw(int date, double amount);
	//结算利息，每年1月1日调用一次该函数
	void settle(int date);
	//显示账户信息
	void show();
};

//SavingsAccount类相关成员函数的实现
SavingsAccount::SavingsAccount(int date, int id, double rate)
	: id(id), balance(0), rate(rate), lastDate(date), accumulation(0) {
	cout << date << "\t#" << id << " is created" << endl;
}

void SavingsAccount::record(int date, double amount) {
	accumulation = accumulate(date);
	lastDate = date;
	amount = floor(amount * 100 + 0.5) / 100;	//保留小数点后两位
	balance += amount;
	cout << date << "\t#" << id << "\t" << amount << "\t" << balance << endl;
}

void SavingsAccount::deposit(int date, double amount) {
	record(date, amount);
}

void SavingsAccount::withdraw(int date, double amount) {
	if (amount > getBalance())
		cout << "Error: not enough money" << endl;
	else
		record(date, -amount);
}

void SavingsAccount::settle(int date) {
	double interest = accumulate(date) * rate / 365;	//计算年息
	if (interest != 0)
		record(date, interest);
	accumulation = 0;
}

void SavingsAccount::show() {
	cout << "#" << id << "\tBalance: " << balance;
}

int main() {
	//建立几个账户
	SavingsAccount sa0(1, 21325302, 0.015);
	SavingsAccount sa1(1, 58320212, 0.015);

	//几笔账目
	sa0.deposit(5, 5000);
	sa1.deposit(25, 10000);
	sa0.deposit(45, 5500);
	sa1.withdraw(60, 4000);

	//开户后第90天到了银行的计息日，结算所有账户的年息
	sa0.settle(90);
	sa1.settle(90);

	//输出各个账户信息
	sa0.show();	cout << endl;
	sa1.show();	cout << endl;
	return 0;
}

C++运行结果

Java代码

public class SavingsAccount {
		private int id;				//账号
		private double balance;		//余额
		private double rate;		//存款的年利率
		private int lastDate;		//上次变更余额的时期
		private double accumulation;	//余额按日累加之和

		//记录一笔帐，date为日期，amount为金额，desc为说明
		private void record(int date, double amount) {
			accumulation = accumulate(date);
			lastDate = date;
			amount = Math.floor((amount * 100 + 0.5)/100);//保留小数点后两位
			balance += amount;
			System.out.println(date+"\t#"+id+"\t"+ amount+"\t"+ balance+"\n");
		}
		//获得到指定日期为止的存款金额按日累积值
		private final double accumulate(int date)  {
			return accumulation + balance * (date - lastDate);
		}
	
		//构造函数
		SavingsAccount(int date, int id, double rate) {
		this.id=id;
		this.balance=0;
		this.rate=rate;
		this.lastDate=date;
		this.accumulation=0; 
		System.out.println( date+"\t#"+id + " is created" +"\n");
	}
		int getId() { return id; }
		double getBalance() { return balance; }
		double getRate() { return rate; }

		//存入现金
		void deposit(int date, double amount) {
			record(date, amount);
		}
		//取出现金
		void withdraw(int date, double amount) {
			if (amount > getBalance())
				System.out.println( "Error: not enough money\n");
			else
				record(date, -amount);
		}
		//结算利息，每年1月1日调用一次该函数
		void settle(int date) {
			double interest = accumulate(date) * rate / 365;	//计算年息
			if (interest != 0)
				record(date, interest);
			accumulation = 0;
		}
		//显示账户信息
		void show() {
			System.out.println("#" + id + "\tBalance: " + balance);
		}

	
public static void main(String[] args) {
		//建立几个账户
		SavingsAccount sa0=new SavingsAccount(1, 21325302, 0.015);
		SavingsAccount sa1=new SavingsAccount(1, 58320212, 0.015);

		//几笔账目
		sa0.deposit(5, 5000);
		sa1.deposit(25, 10000);
		sa0.deposit(45, 5500);
		sa1.withdraw(60, 4000);

		//开户后第90天到了银行的计息日，结算所有账户的年息
		sa0.settle(90);
		sa1.settle(90);

		//输出各个账户信息
		sa0.show();	System.out.println();
		sa1.show();	System.out.println();
	}
}

Java运行结果